Practice Free 312-50v13 Certified Ethical Hacker Exam (CEHv13) Exam Questions Answers With Explanation

In this attack KRACK is an acronym for Key Reinstallation Attack. KRACK may be a severe replay attack on Wi-Fi Protected Access protocol (WPA2), which secures your Wi-Fi connection. Hackers use KRACK to take advantage of a vulnerability in WPA2. When in close range of a possible victim, attackers can access and skim encrypted data using KRACK.

How KRACK Works

Your Wi-Fi client uses a four-way handshake when attempting to attach to a protected network. The handshake confirms that both the client — your smartphone, laptop, et cetera — and therefore the access point share the right credentials, usually a password for the network. This establishes the Pairwise passkey (PMK), which allows for encoding .

Overall, this handshake procedure allows for quick logins and connections and sets up a replacement encryption key with each connection. this is often what keeps data secure on Wi-Fi connections, and every one protected Wi-Fi connections use the four-way handshake for security. This protocol is that the reason users are encouraged to use private or credential-protected Wi-Fi instead of public connections.

KRACK affects the third step of the handshake, allowing the attacker to control and replay the WPA2 encryption key to trick it into installing a key already in use. When the key’s reinstalled, other parameters related to it — the incremental transmit packet number called the nonce and therefore the replay counter — are set to their original values.

Rather than move to the fourth step within the four-way handshake, nonce resets still replay transmissions of the third step. This sets up the encryption protocol for attack, and counting on how the attackers replay the third-step transmissions, they will take down Wi-Fi security.

Why KRACK may be a Threat

Think of all the devices you employ that believe Wi-Fi. it isn’t almost laptops and smartphones; numerous smart devices now structure the web of Things (IoT). due to the vulnerability in WPA2, everything connected to Wi-Fi is in danger of being hacked or hijacked.

Attackers using KRACK can gain access to usernames and passwords also as data stored on devices. Hackers can read emails and consider photos of transmitted data then use that information to blackmail users or sell it on the Dark Web.

Theft of stored data requires more steps, like an HTTP content injection to load malware into the system. Hackers could conceivably take hold of any device used thereon Wi-Fi connection. Because the attacks require hackers to be on the brink of the target, these internet security threats could also cause physical security threats.

On the opposite hand, the necessity to be in close proximity is that the only excellent news associated with KRACK, as meaning a widespread attack would be extremely difficult.

Victims are specifically targeted. However, there are concerns that a experienced attacker could develop the talents to use HTTP content injection to load malware onto websites to make a more widespread affect.

Everyone is in danger from KRACK vulnerability. Patches are available for Windows and iOS devices, but a released patch for Android devices is currently in question (November 2017). There are issues with the discharge , and lots of question if all versions and devices are covered.

The real problem is with routers and IoT devices. These devices aren’t updated as regularly as computer operating systems, and for several devices, security flaws got to be addressed on the manufacturing side. New devices should address KRACK, but the devices you have already got in your home probably aren’t protected.

The best protection against KRACK is to make sure any device connected to Wi-Fi is patched and updated with the newest firmware. that has checking together with your router’s manufacturer periodically to ascertain if patches are available.

The safest connection option may be a private VPN, especially when publicly spaces. If you would like a VPN for private use, avoid free options, as they need their own security problems and there’ll even be issues with HTTPs. Use a paid service offered by a trusted vendor like Kaspersky. Also, more modern networks use WPA3 for better security.

Avoid using public Wi-Fi, albeit it’s password protection. That password is out there to almost anyone, which reduces the safety level considerably.

All the widespread implications of KRACK and therefore the WPA2 vulnerability aren’t yet clear. what’s certain is that everybody who uses Wi-Fi is in danger and wishes to require precautions to guard their data and devices.

Comprehensive and Detailed Explanation:

An incident checklist is a low-overhead, high-impact solution to improve procedural consistency under pressure. It ensures critical steps are not forgotten during stressful incidents. The checklist can be reused and updated easily and is a recognized best practice in incident response processes.

From CEH v13 Courseware:

Module 19: Incident Response and Forensics ? Incident Handling Procedures

CEH v13 emphasizes that well-secured applications use HTTPS, secure cookies, and session regeneration to defend against common session hijacking techniques. In such hardened environments, traditional attacks like session fixation or simple XSS-based token theft often fail because session IDs change at login and secure flags prevent exposure. The remaining viable approach is session token prediction, an advanced attack that analyzes statistical patterns, entropy weaknesses, or timing issues in session ID generation algorithms. CEH discusses that weak pseudorandom number generators (PRNGs) or predictable sequences can allow attackers to compute a valid session ID without intercepting traffic. This method bypasses cookie security and does not rely on manipulating user input, making it suitable for environments with strong defenses. MITM attacks (Option A) require certificate compromise, which is impractical. Session fixation (Option B) fails because the application regenerates tokens. XSS (Option D) is ineffective when secure flags prevent JavaScript access to cookies. Thus, token prediction is the correct answer.

Operational Threat Intelligence provides insights into specific attacker methodologies, motivations, and campaigns. It involves gathering contextual information from real-world attacks, open-source intelligence (OSINT), social media, dark web forums, chat rooms, and human intelligence (HUMINT).

As per CEH v13 Official Courseware:

Operational intelligence is primarily used by security teams to anticipate specific incoming attacks.

It helps provide actionable information such as:

Who is attacking?

Why are they attacking?

What methods are they using?

What infrastructure is involved?

Incorrect Options:

A. Strategic Threat Intelligence is high-level, focusing on long-term trends and business risks.

B. Tactical Threat Intelligence is focused on TTPs (Tactics, Techniques, and Procedures) of known threats, primarily for defenders and analysts.

D. Technical Threat Intelligence includes IoCs like IPs, hashes, and URLs, often short-lived and used for detection systems.

Reference – CEH v13 Official Courseware:

Module 01: Introduction to Ethical Hacking

Section: "Types of Threat Intelligence"

Table: “Strategic vs Tactical vs Operational vs Technical Intelligence”

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DNS spoofing (also known as DNS cache poisoning) occurs when an attacker intercepts or falsifies DNS responses to redirect traffic or exfiltrate data. The appropriate way to prevent such attacks includes:

Implementing DNS anti-spoofing techniques

Using DNSSEC (DNS Security Extensions)

Ensuring proper DNS configurations and validation of responses

From CEH v13:

Module 3: Scanning Networks

Topic: DNS Poisoning and Spoofing Attacks

Defensive Measures: DNS Hardening

CEH v13 Study Guide states:

“To prevent DNS spoofing and cache poisoning, organizations should use DNSSEC, configure anti-spoofing protections, and restrict zone transfers. DNS Anti-spoofing solutions validate responses and ensure data integrity.”

Incorrect Options:

A: Logging may detect but not prevent.

B: Disabling DNS timeouts is unrelated and harmful.

D: Prevents zone transfers, not spoofing specifically.

Comprehensive and Detailed Explanation:

The netstat (network statistics) command is used to display:

Current TCP/UDP connections

Listening ports

Routing tables

Interface statistics

This is one of the most common tools for network troubleshooting and monitoring on Windows and Linux.

From CEH v13 Courseware:

Module 3: Scanning Networks ? System and Network Utilities

The scenario describes an API vulnerability where unauthorized users are able to view, modify, or delete sensitive data by interacting with API objects. This indicates a failure in access control—specifically, a lack of Attribute-Based Access Control (ABAC) validation.

Attribute-Based Access Control (ABAC):

ABAC is an advanced access control model that evaluates access permissions based on attributes of the user, the resource, and the environment (e.g., user role, data sensitivity, location, etc.).

When ABAC is not properly implemented ("No ABAC validation"), APIs may allow users to access or manipulate objects they shouldn't have access to.

In APIs, this typically results in vulnerabilities like Insecure Direct Object Reference (IDOR), where users can tamper with object identifiers (IDs) to access or alter data that doesn’t belong to them.

This is one of the top risks highlighted by the OWASP API Security Top 10 (e.g., Broken Object Level Authorization).

Incorrect Options:

A. Code injection refers to injecting malicious code (e.g., SQLi, XSS), not improper access control.

B. Improper use of CORS (Cross-Origin Resource Sharing) may lead to unauthorized data exposure but doesn’t describe unauthorized object access in an API.

D. Business logic flaws relate to weaknesses in application workflows and rules, not direct access control failures.

Reference – CEH v13 Official Courseware:

Module 14: Hacking Web Applications

Section: "API Security Threats"

Subsection: "Access Control Failures in APIs (IDOR, BOLA, ABAC-related flaws)"

OWASP API Security Top 10: 2023 – A1: Broken Object Level Authorization

CEH iLabs and CEH Engage also demonstrate API-based attack vectors exploiting access control weaknesses.

“Clearing tracks” is a post-exploitation phase in the ethical hacking methodology in which the attacker removes or alters system evidence to hide their activities and avoid detection. This may include:

Deleting or modifying event logs

Clearing bash history or command history

Removing malware traces

Disabling auditing

From CEH v13:

Corrupting or erasing event logs ensures that system administrators or forensic investigators cannot trace the intrusion or determine how the system was compromised.

Incorrect Options:

A. Creating a backdoor is part of the "Maintaining Access" phase, not "Clearing Tracks."

B. Injecting a rootkit is part of the "Gaining or Maintaining Access" stage.

C. Exploiting a vulnerability is part of the "Gaining Access" phase.

Reference – CEH v13 Official Courseware:

Module 05: System Hacking

Section: “Clearing Logs and Erasing Evidence”

Subsection: “Track-Clearing Techniques”

Lab: Log Manipulation and Covering Tracks

A Wireless Intrusion Prevention System (WIPS) is a network device that monitors the radio spectrum for the presence of unauthorized access points (intrusion detection), and can automatically take countermeasures (intrusion prevention).

The described method is a classic example of a Side-Channel Attack, specifically a Timing Attack.

Key characteristics:

It exploits variations in response time from a system to infer sensitive information, such as the correct number of characters in a password.

In this scenario, if a correct character causes a longer processing time, the attacker can deduce the correct sequence iteratively.

According to CEH v13:

Side-channel attacks do not directly break encryption but rely on observing system behavior like timing, power consumption, or electromagnetic leaks.

These attacks are effective against poorly implemented authentication mechanisms or embedded systems like ICS/SCADA.

Incorrect Options:

B. Denial-of-service is aimed at making systems unavailable, not extracting credentials.

C. HMI-based attacks involve manipulating the human-machine interface of ICS systems.

D. Buffer overflow exploits memory handling flaws, not timing behavior.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Cryptanalysis and Side-Channel Attacks”

Subsection: “Timing Attacks and Password Recovery”

According to CEH v13 Module 06: Malware Threats, when analyzing suspicious system behavior or investigating a suspected Trojan infection, a common and effective approach is to:

Monitor system activity and network behavior using tools like netstat, Wireshark, and TCPView.

Trojans often create covert channels or backdoors for remote access, which can be identified through unexpected or unauthorized outgoing connections to remote IP addresses or domains.

Using netstat -an or netstat -ano helps identify open ports and active connections, and checking these against known IPs can indicate whether a Trojan is communicating with a Command and Control (C&C) server.

Analysis of Each Option:

A. Use ExifTool and check for malicious content

Incorrect. ExifTool is primarily used for extracting metadata from files, especially images and documents. It is not effective for analyzing executable malware or system behavior post-execution.

B. You do not check; rather, you immediately restore a previous snapshot of the operating system

Incorrect. While restoring from a snapshot might eventually be required, immediate restoration without diagnosis is not a recommended or forensically sound first step. It also prevents root cause analysis.

C. Upload the file to VirusTotal

Partially correct but not sufficient. While uploading the file to VirusTotal is a good step to confirm if the file is known malware, it does not identify whether the machine is currently infected or actively compromised.

D. Use netstat and check for outgoing connections to strange IP addresses or domains

Correct. This method helps detect if the system is making suspicious external connections that are common in Trojan infections.

Reference from CEH v13 Study Guide and Course Materials:

CEH v13 Official Module 06 – Malware Threats, Section: Types of Malware – Trojans, and System Monitoring Tools

CEH v13 eCourseware Lab Manual: "Detecting Trojan Activity using netstat and TCPView"

CEH Engage Range: Malware Investigation Phase – Trojan Behavior Detection

The host command in Linux is used for DNS lookup operations. The switch -t specifies the type of DNS record you are querying.

host -t a domain.com queries for A (Address) records, which return the IP address associated with a domain.

host -t ns queries for name servers (NS records).

host -t soa queries for the Start of Authority (SOA) record.

host -t AXFR attempts a zone transfer (not a standard resolution method and typically blocked).

Hence, option A correctly resolves a domain name to its IP address.

In CEH v13 Module 07: Evading IDS, Firewalls, and Honeypots, various honeypot detection techniques are discussed. One such method is time-based TCP fingerprinting, which is effective against Honeyd-based honeypots.

Honeyd Honeypots:

Lightweight, low-interaction honeypots.

Often respond with inconsistent or delayed TCP timestamps.

Can be fingerprinted by comparing round-trip time and TTL values to real systems.

Option Clarification:

A. VMware detection: Uses CPU/BIOS identifiers and MAC address patterns.

B. Honeyd detection: Correct — uses time-based TCP fingerprinting.

C. Snort_inline: A network-based IPS, not the context here.

D. Sebek: Used to monitor user-level activity, not related to TCP response timing.

The CEH web server attack methodology describes reconnaissance as a key phase, where testers gather publicly available information before attempting exploitation. Robots.txt is commonly used by administrators to instruct web crawlers about which directories should not be indexed. CEH emphasizes that attackers regularly review robots.txt because it often exposes sensitive directories unintentionally, providing valuable intelligence about internal structure, configuration paths, administrative pages, and potential weak points. In this scenario, the tester observes “Disallow” entries and then discovers the directories are not protected by authentication, allowing direct access to sensitive files. This falls under information gathering through exposed indexing instructions rather than directory traversal, which involves path-manipulation exploits. The tester is not altering file paths or inserting traversal sequences; instead, they are reviewing publicly available indexing instructions and discovering misconfigured access controls. This perfectly aligns with the reconnaissance phase of the CEH methodology, where attackers learn about server architecture using passive or minimally intrusive techniques.

In CEH v13 Module 06: Malware Threats, a worm is described as a self-replicating piece of malware that spreads independently from one system to another without needing to attach itself to any file or program (unlike viruses).

Key Characteristics of Worms:

Capable of network propagation without human interaction.

Often used in mass attacks (e.g., WannaCry, Conficker).

Can cause significant damage by:

Consuming bandwidth.

Spreading payloads (e.g., ransomware).

Modifying or deleting files.

Option Clarification:

A. Rootkit: Hides presence of malware or attacker activities.

B. Trojan: Disguised as legitimate software; does not replicate.

C. Worm: Correct – self-replicating and spreads automatically.

D. Adware: Primarily shows ads; not typically destructive or self-replicating.

To start the Computer Management Console from command line just type compmgmt.msc /computer:computername in your run box or at the command line and it should automatically open the Computer Management console.

TCP port 48101 uses the Transmission management Protocol. transmission control protocol is one in all the most protocols in TCP/IP networks. transmission control protocol could be a connection-oriented protocol, it needs acknowledgement to line up end-to-end communications. only a association is about up user’s knowledge may be sent bi-directionally over the association.

Attention! transmission control protocol guarantees delivery of knowledge packets on port 48101 within the same order during which they were sent. bonded communication over transmission control protocol port 48101 is that the main distinction between transmission control protocol and UDP. UDP port 48101 wouldn’t have bonded communication as transmission control protocol.

UDP on port 48101 provides Associate in Nursing unreliable service and datagrams might arrive duplicated, out of order, or missing unexpectedly. UDP on port 48101 thinks that error checking and correction isn’t necessary or performed within the application, avoiding the overhead of such process at the network interface level.

UDP (User Datagram Protocol) could be a borderline message-oriented Transport Layer protocol (protocol is documented in IETF RFC 768).

Application examples that always use UDP: vocalisation IP (VoIP), streaming media and period multiplayer games. several internet applications use UDP, e.g. the name System (DNS), the Routing info Protocol (RIP), the Dynamic Host Configuration Protocol (DHCP), the straightforward Network Management Protocol (SNMP).

The Security Account Manager (SAM) file on Windows contains user account information, including password hashes. Hackers target this file to extract credentials for offline cracking using tools like L0phtCrack or Cain & Abel.

From CEH v13 Official Courseware:

Module 6: Malware Threats

Module 4: Enumeration

CEH v13 Study Guide states:

“The SAM file stores hashed user credentials. If attackers gain access to it, they can extract password hashes and perform brute-force or dictionary attacks offline.”

Common locations:

C:\Windows\System32\config\SAM

C:\Windows\Repair\SAM

A low-and-slow scanning technique spreads probe attempts over long intervals, reducing the chance of triggering IDS signatures that rely on detecting rapid or high-volume scans. CEH highlights timing-based evasion as an effective method for reconnaissance against networks with strict perimeter controls.

Most likely have an issue with DNS.

DNS stands for “Domain Name System.” It’s a system that lets you connect to websites by matching human-readable domain names (like example.com) with the server's unique ID where a website is stored.

Think of the DNS system as the internet’s phonebook. It lists domain names with their corresponding identifiers called IP addresses, instead of listing people’s names with their phone numbers. When a user enters a domain name like wpbeginner.com on their device, it looks up the IP address and connects them to the physical location where that website is stored.

NOTE: Often DNS lookup information will be cached locally inside the querying computer or remotely in the DNS infrastructure. There are typically 8 steps in a DNS lookup. When DNS information is cached, steps are skipped from the DNS lookup process, making it quicker. The example below outlines all 8 steps when nothing is cached.

The 8 steps in a DNS lookup:

1. A user types ‘example.com’ into a web browser, and the query travels into the Internet and is received by a DNS recursive resolver;

2. The resolver then queries a DNS root nameserver;

3. The root server then responds to the resolver with the address of a Top-Level Domain (TLD) DNS server (such as .com or .net), which stores the information for its domains. When searching for example.com, our request is pointed toward the .com TLD;

4. The resolver then requests the .com TLD;

5. The TLD server then responds with the IP address of the domain’s nameserver, example.com;

6. Lastly, the recursive resolver sends a query to the domain’s nameserver;

7. The IP address for example.com is then returned to the resolver from the nameserver;

8. The DNS resolver then responds to the web browser with the IP address of the domain requested initially;

Once the 8 steps of the DNS lookup have returned the IP address for example.com, the browser can request the web page:

9. The browser makes an HTTP request to the IP address;

10. The server at that IP returns the webpage to be rendered in the browser.

NOTE 2: DNS primarily uses the User Datagram Protocol (UDP) on port number 53 to serve requests. And if this port is blocked, then a problem arises already in the first step. But the ninth step is performed without problems.

Simple Network Management Protocol (SNMP) enumeration involves querying devices on the network for information such as routing tables, interface statistics, and system details.

Useful tools include:

A. SNMPUtil: A command-line Microsoft utility for sending SNMP requests.

B. SNScan: Tool from Foundstone for SNMP scanning and enumeration.

C. SNMPScan: Lightweight tool for scanning networks for SNMP-enabled devices.

D. SolarWinds IP Network Browser: A commercial tool for graphical SNMP enumeration.

From CEH v13 Courseware:

Module 4: Enumeration

Subsection: SNMP Enumeration Tools

Incorrect Option:

E. NMap can detect SNMP services, but is not specialized for SNMP enumeration like the others.

Comprehensive and Detailed Explanation:

The correct file name is /var/log/auth.log (not auth.fesg). “auth.fesg” is a typo or does not exist by default in Linux systems.

Linux login records include:

/var/log/auth.log – authentication logs

/var/log/wtmp – records login sessions

/var/log/btmp – records failed logins

/var/log/user.log – logs user-level messages (optional)

Therefore, B is not a valid log file.

From CEH v13 Courseware:

Module 6: System Hacking ? Covering Tracks in Linux

A NULL scan is a type of TCP stealth scan where no flags are set in the TCP header. It is used to identify open or closed ports based on how the target responds to this unexpected packet.

Behavior:

If the port is closed ? Target responds with RST (Reset)

If the port is open ? No response (on compliant systems like Unix-based OSes)

From CEH v13 Courseware:

Module 03: Scanning Networks

Topic: TCP Flag Scanning

Subsection: NULL Scan

CEH v13 Study Guide states:

“In a NULL scan, if a target port is closed, the system responds with an RST packet as per RFC 793. If the port is open, it typically does not respond, which allows stealthy enumeration of services.”

Incorrect Options:

A. SYN: Initiated by a SYN scan.

B. ACK: Used in ACK scans.

C/D: Not applicable for NULL scans.

F. No response occurs for open ports, not closed ones.

https://en.wikipedia.org/wiki/Sniffing_attack

To prevent networks from sniffing attacks, organizations and individual users should keep away from applications using insecure protocols, like basic HTTP authentication, File Transfer Protocol (FTP), and Telnet. Instead, secure protocols such as HTTPS, Secure File Transfer Protocol (SFTP), and Secure Shell (SSH) should be preferred. In case there is a necessity for using any insecure protocol in any application, all the data transmission should be encrypted. If required, VPN (Virtual Private Networks) can be used to provide secure access to users.

NOTE: I want to note that the wording "best option" is valid only for the EC-Council's exam since the other options will not help against sniffing or will only help from some specific attack vectors.

The sniffing attack surface is huge. To protect against it, you will need to implement a complex of measures at all levels of abstraction and apply controls at the physical, administrative, and technical levels. However, encryption is indeed the best option of all, even if your data is intercepted - an attacker cannot understand it.

UDP scanning produces reliable "closed" results only when an ICMP Port Unreachable is returned. Silent responses indicate either open ports (no reply expected) or filtered ports (blocks dropping packets). CEH emphasizes that non-responses require retransmission or alternate verification techniques.

https://en.wikipedia.org/wiki/Subnetwork

This is a fairly simple question. You must to understand what a subnet mask is and how it works.

A subnetwork or subnet is a logical subdivision of an IP network.The practice of dividing a network into two or more networks is called subnetting.

Computers that belong to the same subnet are addressed with an identical most-significant bit-group in their IP addresses. This results in the logical division of an IP address into two fields: the network number or routing prefix and the rest field or host identifier. The rest field is an identifier for a specific host or network interface.

The routing prefix may be expressed in Classless Inter-Domain Routing (CIDR) notation written as the first address of a network, followed by a slash character (/), and ending with the bit-length of the prefix. For example, 198.51.100.0/24 is the prefix of the Internet Protocol version 4 network starting at the given address, having 24 bits allocated for the network prefix, and the remaining 8 bits reserved for host addressing. Addresses in the range 198.51.100.0 to 198.51.100.255 belong to this network. The IPv6 address specification 2001:db8::/32 is a large address block with 296 addresses, having a 32-bit routing prefix.

For IPv4, a network may also be characterized by its subnet mask or netmask, which is the bitmask that when applied by a bitwise AND operation to any IP address in the network, yields the routing prefix. Subnet masks are also expressed in dot-decimal notation like an address. For example, 255.255.255.0 is the subnet mask for the prefix 198.51.100.0/24.

Netcat does not support encryption natively. To securely transmit data over the network, the attacker must use a variant like Cryptcat, which adds symmetric encryption to standard netcat functionality.

From CEH v13 Courseware:

Module 8: Sniffing and Secure Communication

CEH v13 Study Guide states:

“Cryptcat is a netcat clone that supports encryption. For secure file transfers or remote shell access, cryptcat is the recommended tool.”

Incorrect Options:

A/B/C: These are invalid or non-existent netcat parameters.

CEH cloud modules explain that side-channel attacks exploit indirect information leakage based on hardware characteristics—such as CPU timing, power usage, cache access patterns, or electromagnetic emissions. In virtualized cloud environments, multiple tenants share the same physical hardware, creating opportunities for attackers to extract sensitive data from neighboring virtual machines. By placing a malicious VM on the same host as the victim, an attacker can measure minute differences in timing during cryptographic operations, allowing them to infer private keys or sensitive computations. This aligns precisely with CEH’s definition of a side-channel attack. Cryptojacking involves unauthorized cryptocurrency mining, CPDoS targets caching layers rather than key extraction, and metadata spoofing manipulates cloud metadata endpoints. Only side-channel analysis matches the described attack behavior.

Social engineering is the term used for a broad range of malicious activities accomplished through human interactions. It uses psychological manipulation to trick users into making security mistakes or giving away sensitive information.

Social engineering attacks typically involve some form of psychological manipulation, fooling otherwise unsuspecting users or employees into handing over confidential or sensitive data. Commonly, social engineering involves email or other communication that invokes urgency, fear, or similar emotions in the victim, leading the victim to promptly reveal sensitive information, click a malicious link, or open a malicious file. Because social engineering involves a human element, preventing these attacks can be tricky for enterprises.

https://www.cisco.com/c/en/us/support/docs/ip/access-lists/26448-ACLsamples.html

Since the first line prohibits any TCP traffic (access-list 102 deny tcp any any), the lines below will simply be ignored by the router. Below you will find the example from CISCO documentation.

This figure shows that FTP (TCP, port 21) and FTP data (port 20) traffic sourced from NetB destined to NetA is denied, while all other IP traffic is permitted.

FTP uses port 21 and port 20. TCP traffic destined to port 21 and port 20 is denied and everything else is explicitly permitted.

access-list 102 deny tcp any any eq ftp

access-list 102 deny tcp any any eq ftp-data

access-list 102 permit ip any any

CEH v13 highlights that multi-vector DDoS attacks require multi-layer DDoS mitigation services, often cloud-based, capable of analyzing, filtering, and scrubbing traffic across network, transport, and application layers. These providers maintain massive bandwidth capacity, global scrubbing centers, and behavioral analysis engines that distinguish legitimate sessions from malicious floods. SYN floods and HTTP GET floods require different mitigation techniques simultaneously, which typical firewalls or WAFs cannot handle without dropping legitimate traffic. Blocking SYN packets (Option A) would disrupt normal users. A WAF (Option C) handles only Layer 7 traffic and does not mitigate network-layer volumetric attacks. Increasing bandwidth (Option D) is ineffective against large botnet attacks. Therefore, deploying a multi-layer cloud DDoS protection service is the most effective solution for resilient, real-time mitigation.

Jamming and scrambling are attacks targeting the physical layer of the OSI model, often affecting wireless communication by generating interference to disrupt signal transmission. To mitigate such attacks, one advanced countermeasure is the use of Cognitive Radios.

According to CEH v13 Official Courseware:

Cognitive radios are intelligent radio systems capable of sensing the radio frequency (RF) environment and dynamically adjusting their operating parameters (e.g., frequency, modulation) to avoid interference and jamming.

They enable dynamic spectrum access and help in improving spectrum efficiency and resilience against jamming.

This approach falls under physical-layer security mechanisms.

Incorrect Options:

A. gets and strcpy are unsafe functions vulnerable to buffer overflow, not relevant to DoS protection.

B. Allowing all types of packets increases risk and is not a mitigation.

D. TCP SYN cookies protect against SYN flood attacks and disabling them weakens security.

Reference – CEH v13 Official Courseware:

Module 10: Denial-of-Service (DoS) Attacks

Section: “Defensive Strategies Against Jamming and DoS Attacks”

Subsection: “Physical Layer Countermeasures”

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A demilitarized zone (DMZ) is a buffer zone between a trusted internal network and an untrusted external network (usually the internet). Public-facing services like web servers, email servers, and DNS servers are typically placed in the DMZ. These nodes can be accessed from the internet, but the DMZ design ensures that unauthorized access to the internal network is blocked or highly restricted.

The purpose is to provide access to certain systems without exposing the internal network directly.

Well-known and widely used password-cracking tools include:

A. L0phtcrack – Windows password auditing tool that can crack LM and NTLM hashes.

E. John the Ripper – Versatile password cracker that supports many hash types on Unix, Windows, etc.

Incorrect Options:

B. NetCat – A network tool used for port scanning and data transfer.

C. “Jack the Ripper” is likely a mistaken reference to John the Ripper.

D. Netbus – A remote access Trojan, not a password cracker.

From CEH v13 Courseware:

Module 6: Password Cracking Tools

A rootkit is a type of stealth malware designed to hide the existence of certain processes or programs from normal detection methods. It can:

Hide itself and other processes

Conceal files and registry entries

Intercept system calls or keystrokes (keylogging)

Maintain persistent access

From CEH v13 Courseware:

Module 6: Malware Threats ? Rootkits

Incorrect Options:

A: A Trojan may offer remote access but doesn't necessarily hide itself.

C: DoS tools are used to overload systems, not hide.

D: Scanners detect vulnerabilities, not conceal activities.

E: A backdoor may provide unauthorized access, but rootkits focus on hiding.

A powerful and often the most effective cryptanalysis method in which the attack is directed at the most vulnerable link in the cryptosystem - the person. In this attack, the cryptanalyst uses blackmail, threats, torture, extortion, bribery, etc. This method's main advantage is the decryption time's fundamental independence from the volume of secret information, the length of the key, and the cipher's mathematical strength.

The method can reduce the time to guess a password, for example, for AES, to an acceptable level; however, it requires special authorization from the relevant regulatory authorities. Therefore, it is outside the scope of this course and is not considered in its practical part.

Vulnerability scanning solutions perform vulnerability penetration tests on the organizational network in three steps:

1. Locating nodes: The first step in vulnerability scanning is to locate live hosts in the target network using various scanning techniques.

2. Performing service and OS discovery on them: After detecting the live hosts in the target network, the next step is to enumerate the open ports and services and the operating system on the target systems.

3. Testing those services and OS for known vulnerabilities: Finally, after identifying the open services and the operating system running on the target nodes, they are tested for known vulnerabilities.

 DHCP.MIB: Monitors network traffic between DHCP servers and remote hosts

? HOSTMIB.MIB: Monitors and manages host resources

? LNMIB2.MIB: Contains object types for workstation and server services

? MIBJI.MIB: Manages TCP/IP-based Internet using a simple architecture and system

? WINS.MIB: For the Windows Internet Name Service (WINS)

The ntpq utility provides detailed NTP peer information, synchronization states, offsets, delays, and strata. CEH specifically lists ntpq as the tool for querying NTP daemon status and enumerating peer relationships, making it essential for reconnaissance and lateral movement mapping.

CEH courseware describes rootkits as specialized malware designed to conceal their presence while providing persistent, unauthorized access to system-level functions. Rootkits typically modify low-level components of the operating system—such as kernel modules, drivers, or system processes—to hide files, processes, registry keys, and network connections. Their primary purpose is to grant attackers administrative privileges without triggering alerts, making them extremely stealthy and dangerous. CEH emphasizes that rootkits often accompany other malware to maintain long-term control after initial compromise. In contrast, viruses replicate by attaching to files, keyloggers record keystrokes but do not hide system-level access, and ransomware encrypts data rather than conceals operations. The defining characteristics in this scenario—cloaking activity, providing admin-level control, persisting undetected—are directly aligned with rootkit behavior as described in CEH training material.

CEH v13 identifies Slowloris as a low-bandwidth yet highly effective application-layer DoS technique that works by opening many HTTP connections and sending headers very slowly, never completing the request. Because the server must maintain these half-open HTTP sessions, its connection pool becomes saturated, preventing it from servicing legitimate users. Slowloris is particularly dangerous because it does not rely on malformed packets, high traffic volume, or protocol abuses; instead, it mimics legitimate HTTP behavior, making it difficult for firewalls or IDS systems to distinguish malicious traffic. This aligns exactly with the described scenario, where thousands of legitimate-looking HTTP connections are gradually consuming server resources. Fragmentation attacks (Option B) target packet reconstruction, UDP floods (Option C) generate high-bandwidth noise, and SYN floods (Option D) impact the TCP handshake layer, not the HTTP header behavior. Slowloris’ unique use of slow HTTP headers directly matches the symptoms described.

The total data extracted by the attacker is E=xyz’u’, where x is the number of tables, y is the number of columns, z is the number of records, and u is the number of SQL payloads. To maximize E, the attacker would want to choose the highest values of z and u, while keeping x and y constant. Therefore, the situation where z=600 and u=2 would result in the highest extracted data volume, as E=42600*2=9600. The other situations would result in lower values of E, as shown below:

A: E=42400*4=12800

B: E=42550*2=8800

D: E=42500*3=12000

The attacker uses UNION SELECT statements to combine the results from different tables and columns, and DBMS_XSLPPOCESSOR.READ2CLOB to read sensitive files from the database server12. These techniques can bypass input validation and pattern matching measures that are based on the application’s responses3.

The hosts file on a computer maps domain names to IP addresses locally. By modifying this file, an attacker can redirect traffic destined for legitimate sites (e.g., www.MyPersonalBank.com) to malicious IP addresses (e.g., a phishing server).

The hosts file takes precedence over DNS queries, making it a simple but powerful tool for local redirection.

Windows hosts file location: C:\Windows\System32\drivers\etc\hosts

Linux/Unix hosts file location: /etc/hosts

Reference – CEH v13 Official Study Guide:

Module 6: Malware Threats

Quote:

“Attackers can redirect users to phishing or malware sites by altering the local hosts file, bypassing DNS resolution.”

Incorrect Options:

A. boot.ini is for boot configuration, not DNS resolution.

B. sudoers controls administrative privileges in Linux.

C. networks is for defining network names, not URL resolution.

===========

In the Windows security model, SID ending in -500 is reserved for the built-in Administrator account. The SID seen in the image:

S-1-5-21-343818398-789336058-1343024091-500 ? maps to user Joe

This proves that Joe is the true built-in administrator account on the domain EARTH.

From CEH v13 Courseware:

Module 4: Enumeration

Topic: SID Enumeration and Account Discovery

CEH v13 Study Guide states:

“In Windows, the account with RID 500 is always the default Administrator account. Even if renamed, its SID remains ending in -500. Enumeration of this SID allows attackers to identify privileged accounts.”

Incorrect Options:

A: Incomplete — it is not just that Joe has SID 500, but that SID 500 means Joe is the administrator.

B/C: These commands don’t validate Guest account status.

E: Incorrect — these commands explicitly prove administrator identity.

A dictionary Attack as an attack vector utilized by the attacker to break in a very system, that is password protected, by golf shot technically each word in a very dictionary as a variety of password for that system. This attack vector could be a variety of Brute Force Attack.

The lexicon will contain words from an English dictionary and conjointly some leaked list of commonly used passwords and once combined with common character substitution with numbers, will generally be terribly effective and quick.

How is it done?

Basically, it’s attempting each single word that’s already ready. it’s done victimization machine-controlled tools that strive all the possible words within the dictionary.

Some password Cracking Software:

• John the ripper

• L0phtCrack

• Aircrack-ng

CEH reconnaissance and enumeration modules explain that LDAP services often support anonymous binding by default unless explicitly disabled. Anonymous bind allows unauthenticated users to query certain directory attributes, which can lead to disclosure of usernames, organizational hierarchy, and email addresses—critical information for password attacks, phishing campaigns, and privilege escalation planning. In the scenario described, the tester obtained directory data without providing any credentials, demonstrating that anonymous bind permissions were enabled. LDAPS requires TLS encryption and authentication, which contradicts the observed access. Kerberos authentication mandates valid credentials. LDAP via RADIUS is used for authentication integration, not for information disclosure. Since the query was successful with no authentication and no access controls triggered, this aligns exactly with CEH’s description of anonymous LDAP binding.

Trident is a highly sophisticated spyware tool used in mobile surveillance operations. It exploits multiple zero-day vulnerabilities to jailbreak iPhones remotely and grant full control to the attacker. It is famously associated with the Pegasus spyware, which was able to:

Record calls and ambient sound

Capture screenshots

Read SMS, emails, and contacts

Monitor GPS and application use

As per CEH v13:

Trident uses a chain of exploits to compromise iOS devices without physical access.

It was used in highly targeted attacks against journalists, activists, and government officials.

Incorrect Options:

A. DroidSheep is an Android tool for session hijacking on unsecured Wi-Fi.

B. Androrat is a RAT for Android devices.

C. Zscaler is a cloud security platform, not malware.

Reference – CEH v13 Official Courseware:

Module 17: Hacking Mobile Platforms

Section: “iOS Malware”

Subsection: “Spyware like Trident and Pegasus”

===========

The scenario describes a method used to make a cryptographic key more secure by making it harder to brute-force. This process is called Key Stretching.

Key Stretching:

Takes a weak or short key and processes it through a function (often repeatedly) to produce a stronger, longer key.

Commonly used in password hashing (e.g., bcrypt, PBKDF2, scrypt).

Increases the computational time required to test each guess in a brute-force attack, effectively reducing attack feasibility.

Incorrect Options:

A. Key derivation function (KDF) is related but more general; key stretching is a specific technique often implemented within KDFs.

B. Key reinstallation is associated with WPA2 KRACK attacks.

C. Public key infrastructure (PKI) is a system of digital certificates, not a key strengthening technique.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Password Hashing and Key Stretching Techniques”

Subsection: “bcrypt, PBKDF2, and Key Strengthening”

CEH iLab: Password Hashing and Cracking Simulations

snmp-check (snmp_enum Module) is the best tool to help the ethical hacker to get the information without directly modifying any parameters within the SNMP agent’s MIB. snmp-check is a tool that allows the user to enumerate SNMP devices and extract information from them. It can gather a wide array of information about the target, such as system information, network interfaces, routing tables, ARP cache, installed software, running processes, TCP and UDP services, user accounts, and more. snmp-check can also perform brute force attacks to discover the SNMP community strings, which are the passwords used to access the SNMP agent. snmp-check is available as a standalone tool or as a module (snmp_enum) within the Metasploit framework.

The other options are not as effective or suitable as snmp-check for the ethical hacker’s task. Nmap is a network scanning and enumeration tool that can perform various types of scans and probes on the target. It can also run scripts to perform specific tasks, such as retrieving SNMP information. However, Nmap may not be able to gather as much information as snmp-check, and it may also trigger alerts or blocks from firewalls or intrusion detection systems. Oputils is a network monitoring and management toolset that can perform various functions, such as device discovery, configuration backup, bandwidth monitoring, IP address management, and more. However, Oputils is mainly designed for device management and not SNMP enumeration, and it may not be able to extract valuable network information from the SNMP agent. SnmpWalk is a tool that allows the user to retrieve the entire MIB tree of an SNMP agent by using SNMP GETNEXT requests. However, SnmpWalk is not suitable for the ethical hacker’s task, because it requires the user to change an OID (object identifier) to a different value, which may modify the parameters within the SNMP agent’s MIB and affect its functionality or security. References:

snmp-check - The SNMP enumerator

SNMP Enumeration | Ethical Hacking - GreyCampus

SNMP Enumeration - GeeksforGeeks

Nmap - the Network Mapper - Free Security Scanner

OpUtils - Network Monitoring & Management Toolset

SnmpWalk - SNMP MIB Browser

«Many IDS reassemble communication streams; hence, if a packet is not received within a reasonable period, many IDS stop reassembling and handling that stream. If the application under attack keeps a session active for a longer time than that spent by the IDS on reassembling it, the IDS will stop. As a result, any session after the IDS stops reassembling the sessions will be susceptible to malicious data theft by attackers. The IDS will not log any attack attempt after a successful splicing attack. Attackers can use tools such as Nessus for session splicing attacks.»

Did you know that the EC-Council exam shows how well you know their official book? So, there is no "Whisker" in it. In the chapter "Evading IDS" -> "Session Splicing", the recommended tool for performing a session-splicing attack is Nessus. Where Wisker came from is not entirely clear, but I will assume the author of the question found it while copying Wikipedia.

https://en.wikipedia.org/wiki/Intrusion_detection_system_evasion_techniques

One basic technique is to split the attack payload into multiple small packets so that the IDS must reassemble the packet stream to detect the attack. A simple way of splitting packets is by fragmenting them, but an adversary can also simply craft packets with small payloads. The 'whisker' evasion tool calls crafting packets with small payloads 'session splicing'.

By itself, small packets will not evade any IDS that reassembles packet streams. However, small packets can be further modified in order to complicate reassembly and detection. One evasion technique is to pause between sending parts of the attack, hoping that the IDS will time out before the target computer does. A second evasion technique is to send the packets out of order, confusing simple packet re-assemblers but not the target computer.

NOTE: Yes, I found scraps of information about the tool that existed in 2012, but I can not give you unverified information. According to the official tutorials, the correct answer is Nessus, but if you know anything about Wisker, please write in the QA section. Maybe this question will be updated soon, but I'm not sure about that.

Web server footprinting is part of the reconnaissance phase in ethical hacking. It involves gathering detailed information about a web server’s structure, external links, available directories, scripts, and technologies in use.

Techniques include:

Spidering the site to map all accessible URLs and file paths

Identifying hidden directories or backup files

Analyzing page structures and URL patterns

This information helps attackers identify areas to target for further scanning or exploitation.

Incorrect Options:

A. Vulnerability scanning is active testing, not passive footprinting.

C. System-level data is gathered in OS or network footprinting.

D. Brute-force attacks are exploitation techniques, not reconnaissance.

Reference – CEH v13 Official Courseware:

Module 02: Footprinting and Reconnaissance

Section: “Web Server Footprinting Techniques”

Tool Reference: HTTrack, Burp Spider, OWASP ZAP

===========

Hashing algorithms are specifically designed to ensure data integrity. A hash function takes an input and returns a fixed-length string, called a hash or message digest. Even a small change in the input results in a completely different hash, making it useful for detecting tampering.

Common hashing algorithms include:

MD5 (now obsolete for secure uses)

SHA-1, SHA-2, SHA-3

HMAC (Hashed Message Authentication Code)

From CEH v13 Courseware:

Module 20: Cryptography

Topic: Hash Functions and Data Integrity

CEH v13 Study Guide states:

“Hashing algorithms provide integrity by generating a unique digital fingerprint of data. Any alteration in the message content will result in a different hash value, indicating that the integrity has been compromised.”

Incorrect Options:

A: Symmetric algorithms provide confidentiality.

B: Asymmetric algorithms provide confidentiality and authentication.

D: "Integrity algorithms" is not a formal cryptographic term.

Operational Technology and ICS environments often suffer from misconfigurations such as unchanged factory-default passwords. CEH identifies exploiting default credentials as a direct and effective method because ICS devices frequently lack strong authentication controls. Using these built-in credentials grants immediate unauthorized access to supervisory controls, enabling adversaries to manipulate configurations, disrupt processes, or escalate attacks across critical systems.

document.write(); (Cookie and session ID theft)

https://www.softwaretestinghelp.com/cross-site-scripting-xss-attack-test/

As seen in the indicated question, cookies are escaped and sent to script to variable ‘cookie’. If the malicious user would inject this script into the website’s code, then it will be executed in the user’s browser and cookies will be sent to the malicious user.

A white hat (or a white hat hacker) is an ethical computer hacker, or a computer security expert, who focuses on penetration testing and in other testing methodologies that ensures the safety of an organization’s information systems. Ethical hacking may be a term meant to imply a broader category than simply penetration testing. Contrasted with black hat, a malicious hacker, the name comes from Western films, where heroic and antagonistic cowboys might traditionally wear a white and a black hat respectively. While a white hat hacker hacks under good intentions with permission, and a black hat hacker, most frequently unauthorized, has malicious intent, there’s a 3rd kind referred to as a gray hat hacker who hacks with good intentions but sometimes without permission.

White hat hackers can also add teams called “sneakers and/or hacker clubs”,red teams, or tiger teams.

While penetration testing concentrates on attacking software and computer systems from the beginning – scanning ports, examining known defects in protocols and applications running on the system and patch installations, as an example – ethical hacking may include other things. A full-blown ethical hack might include emailing staff to invite password details, searching through executive’s dustbins and typically breaking and entering, without the knowledge and consent of the targets. Only the owners, CEOs and Board Members (stake holders) who asked for such a censoring of this magnitude are aware. to undertake to duplicate a number of the destructive techniques a true attack might employ, ethical hackers may arrange for cloned test systems, or organize a hack late in the dark while systems are less critical. In most up-to-date cases these hacks perpetuate for the long-term con (days, if not weeks, of long-term human infiltration into an organization). Some examples include leaving USB/flash key drives with hidden auto-start software during a public area as if someone lost the tiny drive and an unsuspecting employee found it and took it.

Some other methods of completing these include:

• DoS attacks

• Social engineering tactics

• Reverse engineering

• Network security

• Disk and memory forensics

• Vulnerability research

• Security scanners such as:

– W3af

– Nessus

– Burp suite

• Frameworks such as:

– Metasploit

• Training Platforms

These methods identify and exploit known security vulnerabilities and plan to evade security to realize entry into secured areas. they’re ready to do that by hiding software and system ‘back-doors’ which will be used as a link to information or access that a non-ethical hacker, also referred to as ‘black-hat’ or ‘grey-hat’, might want to succeed in .

To ensure both confidentiality and non-repudiation for secure email communication, you need to use a combination of symmetric and asymmetric cryptography. Symmetric encryption is a method of encrypting and decrypting data using the same secret key, which is faster and more efficient than asymmetric encryption. Asymmetric encryption is a method of encrypting and decrypting data using a pair of keys: a public key and a private key, which are mathematically related but not identical. Asymmetric encryption can provide authentication, integrity, and non-repudiation, as well as key distribution.

The cryptographic technique that would best serve the purpose is to apply asymmetric encryption with RSA and use the private key for signing. RSA is a widely used algorithm for asymmetric encryption, which is based on the difficulty of factoring large numbers. RSA can be used to encrypt data, as well as to generate digital signatures, which are a way of proving the identity and authenticity of the sender and the integrity of the message.

The steps to implement this technique are as follows1:

Generate a pair of keys for each user: a public key and a private key. The public key can be shared with anyone, while the private key must be kept secret and protected by the user.

When a user wants to send an email to another user, they first encrypt the email content with a symmetric key, such as AES, which is a strong and efficient algorithm for symmetric encryption. The symmetric key is then encrypted with the recipient’s public key, using RSA. The encrypted email and the encrypted symmetric key are then sent to the recipient.

The sender also generates a digital signature for the email, using their private key and a hash function, such as SHA-256, which is a secure and widely used algorithm for generating hashes. A hash function is a mathematical function that takes any input and produces a fixed-length output, called a hash or a digest, that uniquely represents the input. A digital signature is a hash of the email that is encrypted with the sender’s private key, using RSA. The digital signature is then attached to the email and sent to the recipient.

When the recipient receives the email, they first decrypt the symmetric key with their private key, using RSA. They then use the symmetric key to decrypt the email content, using AES. They also verify the digital signature by decrypting it with the sender’s public key, using RSA, and comparing the resulting hash with the hash of the email, using the same hash function. If the hashes match, it means that the email is authentic and has not been tampered with.

Using this technique, the email communication is secure because:

The confidentiality of the email content is ensured by the symmetric encryption with AES, which is hard to break without knowing the symmetric key.

The symmetric key is also protected by the asymmetric encryption with RSA, which is hard to break without knowing the recipient’s private key.

The non-repudiation of the email is ensured by the digital signature with RSA, which is hard to forge without knowing the sender’s private key.

The digital signature also provides authentication and integrity of the email, as it proves that the email was sent by the sender and has not been altered in transit.

False Positives occur when a scanner, Web Application Firewall (WAF), or Intrusion Prevention System (IPS) flags a security vulnerability that you do not have. A false negative is the opposite of a false positive, telling you that you don't have a vulnerability when, in fact, you do.

A false positive is like a false alarm; your house alarm goes off, but there is no burglar. In web application security, a false positive is when a web application security scanner indicates that there is a vulnerability on your website, such as SQL Injection, when, in reality, there is not. Web security experts and penetration testers use automated web application security scanners to ease the penetration testing process. These tools help them ensure that all web application attack surfaces are correctly tested in a reasonable amount of time. But many false positives tend to break down this process. If the first 20 variants are false, the penetration tester assumes that all the others are false positives and ignore the rest. By doing so, there is a good chance that real web application vulnerabilities will be left undetected.

When checking for false positives, you want to ensure that they are indeed false. By nature, we humans tend to start ignoring false positives rather quickly. For example, suppose a web application security scanner detects 100 SQL Injection vulnerabilities. If the first 20 variants are false positives, the penetration tester assumes that all the others are false positives and ignore all the rest. By doing so, there are chances that real web application vulnerabilities are left undetected. This is why it is crucial to check every vulnerability and deal with each false positive separately to ensure false positives.

Adversaries could decide to build an possible or file difficult to find or analyze by encrypting, encoding, or otherwise obfuscating its contents on the system or in transit. this is often common behavior which will be used across totally different platforms and therefore the network to evade defenses.

Payloads may be compressed, archived, or encrypted so as to avoid detection. These payloads may be used throughout Initial Access or later to mitigate detection. typically a user’s action could also be needed to open and Deobfuscate/Decode Files or info for User Execution. The user can also be needed to input a parole to open a parole protected compressed/encrypted file that was provided by the mortal. Adversaries can also used compressed or archived scripts, like JavaScript.

Portions of files can even be encoded to cover the plain-text strings that will otherwise facilitate defenders with discovery. Payloads can also be split into separate, ostensibly benign files that solely reveal malicious practicality once reassembled.

Adversaries can also modify commands dead from payloads or directly via a Command and Scripting Interpreter. surroundings variables, aliases, characters, and different platform/language specific linguistics may be wont to evade signature based mostly detections and application management mechanisms.

Snort is an open-source Network Intrusion Detection and Prevention System (NIDS/NIPS) capable of real-time traffic analysis and packet logging. It functions as a sniffer and can detect various forms of attacks using signature-based rules.

CEH v13 Reference:

Module 10: Evading IDS, Firewalls, and Honeypots

"Snort can operate as a sniffer, logger, or full NIDS capable of real-time traffic analysis."

??????????????????????

Two-factor Authentication or 2FA is a user identity verification method, where two of the three possible authentication factors are combined to grant access to a website or application.1) something the user knows, 2) something the user has, or 3) something the user is.

The possible factors of authentication are:

· Something the User Knows:

This is often a password, passphrase, PIN, or secret question. To satisfy this authentication challenge, the user must provide information that matches the answers previously provided to the organization by that user, such as “Name the town in which you were born.”

· Something the User Has:

This involves entering a one-time password generated by a hardware authenticator. Users carry around an authentication device that will generate a one-time password on command. Users then authenticate by providing this code to the organization. Today, many organizations offer software authenticators that can be installed on the user’s mobile device.

· Something the User Is:

This third authentication factor requires the user to authenticate using biometric data. This can include fingerprint scans, facial scans, behavioral biometrics, and more.

For example: In internet security, the most used factors of authentication are:

something the user has (e.g., a bank card) and something the user knows (e.g., a PIN code). This is two-factor authentication. Two-factor authentication is also sometimes referred to as strong authentication, Two-Step Verification, or 2FA.

The key difference between Multi-Factor Authentication (MFA) and Two-Factor Authentication (2FA) is that, as the term implies, Two-Factor Authentication utilizes a combination of two out of three possible authentication factors. In contrast, Multi-Factor Authentication could utilize two or more of these authentication factors.

DHCP starvation is a network-level attack in which an attacker sends a massive number of DHCPDISCOVER requests, each appearing to originate from a different MAC address. CEH courseware explains that DHCP servers assign IP leases based on unique MAC addresses, and when the lease pool is exhausted, legitimate clients are unable to obtain valid IP configurations. This disrupts network connectivity and can serve as a precursor to deploying a rogue DHCP server, enabling further attacks such as traffic redirection or credential interception. DHCP starvation is different from ARP spoofing, which manipulates MAC–IP mappings, or DNS poisoning, which corrupts domain resolution. Rogue DHCP relay attacks involve forwarding DHCP packets to unauthorized servers, not depleting leases. The scenario described—rapid MAC address spoofing and exhaustion of DHCP leases—matches the precise definition of DHCP starvation as documented in CEH materials.

Passive OS fingerprinting involves observing traffic from a remote host and analyzing it to infer details about the operating system without actively sending packets or probes. This is useful in stealthy reconnaissance where avoiding detection is critical.

tcpdump is a packet analyzer that captures traffic in real time. By analyzing certain TCP/IP header fields such as TTL (Time-To-Live), window size, TCP options, and DF (Don't Fragment) flags, attackers can passively deduce the operating system of the target host.

CEH v13 Guide states:

“Passive fingerprinting tools like tcpdump and Wireshark allow the attacker to capture packets and analyze them for OS-specific traits, making it possible to identify the OS without sending packets to the target system.”

Reference – CEH v13 Study Guide:

Module 02: Footprinting and Reconnaissance, Section: “OS Fingerprinting Techniques”, Subsection: “Passive OS Fingerprinting”

Incorrect Options Explained:

A: nmap is primarily an active scanning tool (though it has limited passive capabilities).

C: tracert is used for tracing packet routes, not OS fingerprinting.

D: ping checks host availability and latency, not OS details.

???????????????

1. AV (Asset value) = $300 + (14 * $10) = $440 - the cost of a hard drive plus the work of a recovery person, i.e.how much would it take to replace 1 asset? 10 hours for resorting the OS and soft + 4 hours for DB restore multiplies by hourly rate of the recovery person.

2. SLE (Single Loss Expectancy) = AV * EF (Exposure Factor) = $440 * 1 = $440

3. ARO (Annual rate of occurrence) = 1/3 (every three years, meaning the probability of occurring during 1 years is 1/3)

4. ALE (Annual Loss Expectancy) = SLE * ARO = 0.33 * $440 = $145.2

CEH methodology emphasizes validating and researching identified vulnerabilities to determine exploitability, patch status, and business impact. Even medium-risk findings require investigation to assess their real severity.

Social engineering attacks that target business processes are especially effective when they mimic legitimate workflows. CEH learning materials emphasize that attackers often exploit trust relationships and organizational procedures rather than attempting broad or generic phishing methods. In the context of HR operations, onboarding portals are highly trusted and frequently accessed by new employees who expect to enter personal information, submit documents, and receive initial network credentials. By creating a fake onboarding portal that closely resembles the organization’s internal system, an attacker can collect credentials without triggering suspicion because the action being requested appears normal and expected. This method leverages procedural familiarity, brand consistency, and the implied authority of HR communications, making it far more effective than generic phishing emails or unsolicited social media messages. Phone calls, while sometimes useful, involve real-time interaction and increase the chance of detection. The fake portal, however, seamlessly integrates into existing processes, making it the most effective and lowest-profile approach for acquiring network credentials.

These tools are all Distributed Denial of Service (DDoS) attack tools that coordinate large numbers of systems (bots) to flood target networks or services:

Trinoo – UDP flood-based DDoS tool

TFN2k (Tribe Flood Network 2000) – Supports ICMP, SYN, and other attack types

WinTrinoo – Windows variant of Trinoo

Stacheldraht – Combines features of Trinoo and TFN with encryption and auto-updating

T-Sight – DDoS control tool

From CEH v13 Official Courseware:

Module 9: Denial-of-Service Attacks

CEH v13 Study Guide states:

“These tools are classic examples of distributed DoS platforms used by attackers to launch coordinated flood attacks using compromised hosts.”

Incorrect Options:

A: Not all tools were developed by the same group.

B: Not typically used by defenders.

D/E: These tools are cross-platform (some run on Linux, others on Windows).

Syhunt Hybrid combines comprehensive static and dynamic security scans to detect vulnerabilities like XSS, File Inclusion, SQL Injection, Command Execution and many more, including inferential, in-band and out-of-band attacks through Hybrid-Augmented Analysis (HAST). With Syhunt's unique gray box/hybrid scanning capability the information acquired during source code scans is automatically used to create and enhance dynamic scans. All entry points are covered generating detailed information about the security level of your web applications. Available for on-premises deployment for businesses using Windows and Linux 64-bit.

Web Server Security Tools - Web Application Security Scanners The Syhunt Hybrid scanner automates web application security testing and guards the organization’s web infrastructure against web application security threats. Syhunt Dynamic crawls websites and detects XSS, directory transversal problems, fault injection, SQL injection, attempts to execute commands, and several other attacks. (P.1713/1697)

CEH v13 outlines insertion attacks as IDS evasion methods in which attackers send packets deliberately crafted so that the IDS processes them differently from the target host. In an insertion attack, malformed packets appear legitimate to the IDS—allowing malicious traffic to blend with benign inspection results—while the end host rejects or modifies the packets due to incorrect checksums, invalid flags, or protocol inconsistencies. As a result, the IDS sees one set of reconstructed data, while the actual host processes a different version or nothing at all. CEH emphasizes that intrusion detection systems may not follow full TCP/IP stack validation, making them susceptible to deception by malformed or borderline-conformant packets. Polymorphic shellcode (Option B) changes payload signatures, not packet structure. Session splicing (Option C) splits payload across packets to evade pattern matching but does not rely on checksum manipulation. Fragmentation attacks (Option D) divide traffic into smaller fragments, not alter validity fields. The described behavior fits insertion attacks precisely.

DNS uses Ports 53 which is almost always open on systems, firewalls, and clients to transmit DNS queries. instead of the more familiar Transmission Control Protocol (TCP) these queries use User Datagram Protocol (UDP) due to its low-latency, bandwidth and resource usage compared TCP-equivalent queries. UDP has no error or flow-control capabilities, nor does it have any integrity checking to make sure the info arrived intact.

How is internet use (browsing, apps, chat etc) so reliable then? If the UDP DNS query fails (it’s a best-effort protocol after all) within the first instance, most systems will retry variety of times and only after multiple failures, potentially switch to TCP before trying again; TCP is additionally used if the DNS query exceeds the restrictions of the UDP datagram size – typically 512 bytes for DNS but can depend upon system settings.

Figure 1 below illustrates the essential process of how DNS operates: the client sends a question string (for example, mail.google[.]com during this case) with a particular type – typically A for a number address. I’ve skipped the part whereby intermediate DNS systems may need to establish where ‘.com’ exists, before checking out where ‘google[.]com’ are often found, and so on.

Many worms and scanners are created to seek out and exploit systems running telnet. Given these facts, it’s really no surprise that telnet is usually seen on the highest Ten Target Ports list. Several of the vulnerabilities of telnet are fixed. They require only an upgrade to the foremost current version of the telnet Daemon or OS upgrade. As is usually the case, this upgrade has not been performed on variety of devices. this might flow from to the very fact that a lot of systems administrators and users don’t fully understand the risks involved using telnet. Unfortunately, the sole solution for a few of telnets vulnerabilities is to completely discontinue its use. the well-liked method of mitigating all of telnets vulnerabilities is replacing it with alternate protocols like ssh. Ssh is capable of providing many of an equivalent functions as telnet and a number of other additional services typical handled by other protocols like FTP and Xwindows. Ssh does still have several drawbacks to beat before it can completely replace telnet. it’s typically only supported on newer equipment. It requires processor and memory resources to perform the info encryption and decryption. It also requires greater bandwidth than telnet thanks to the encryption of the info . This paper was written to assist clarify how dangerous the utilization of telnet are often and to supply solutions to alleviate the main known threats so as to enhance the general security of the web

Once a reputation is resolved to an IP caching also helps: the resolved name-to-IP is usually cached on the local system (and possibly on intermediate DNS servers) for a period of your time . Subsequent queries for an equivalent name from an equivalent client then don’t leave the local system until said cache expires. Of course, once the IP address of the remote service is understood , applications can use that information to enable other TCP-based protocols, like HTTP, to try to to their actual work, for instance ensuring internet cat GIFs are often reliably shared together with your colleagues.

So, beat all, a couple of dozen extra UDP DNS queries from an organization’s network would be fairly inconspicuous and will leave a malicious payload to beacon bent an adversary; commands could even be received to the requesting application for processing with little difficulty.

We have various articles already in our documentation for setting up SNMPv2 trap handling in Opsview, but SNMPv3 traps are a whole new ballgame. They can be quite confusing and complicated to set up the first time you go through the process, but when you understand what is going on, everything should make more sense.

SNMP has gone through several revisions to improve performance and security (version 1, 2c and 3). By default, it is a UDP port based protocol where communication is based on a ‘fire and forget’ methodology in which network packets are sent to another device, but there is no check for receipt of that packet (versus TCP port when a network packet must be acknowledged by the other end of the communication link). 

There are two modes of operation with SNMP – get requests (or polling) where one device requests information from an SNMP enabled device on a regular basis (normally using UDP port 161), and traps where the SNMP enabled device sends a message to another device when an event occurs (normally using UDP port 162). The latter includes instances such as someone logging on, the device powering up or down, or a wide variety of other problems that would need this type of investigation.

This blog covers SNMPv3 traps, as polling and version 2c traps are covered elsewhere in our documentation.

SNMP traps

Since SNMP is primarily a UDP port based system, traps may be ‘lost’ when sending between devices; the sending device does not wait to see if the receiver got the trap. This means if the configuration on the sending device is wrong (using the wrong receiver IP address or port) or the receiver isn’t listening for traps or rejecting them out of hand due to misconfiguration, the sender will never know.

The SNMP v2c specification introduced the idea of splitting traps into two types; the original ‘hope it gets there’ trap and the newer ‘INFORM’ traps. Upon receipt of an INFORM, the receiver must send an acknowledgement back. If the sender doesn’t get the acknowledgement back, then it knows there is an existing problem and can log it for sysadmins to find when they interrogate the device.

Web Server Attacks - DNS Server Hijacking Attacker compromises the DNS server and changes the DNS settings so that all the requests coming towards the target web server are redirected to his/her own malicious server. (P.1623/1607)

Nmap provides a scripting engine (NSE) that includes a script named http-methods. This script sends OPTIONS requests to the web server to determine which HTTP methods are supported. Identifying risky methods like PUT and DELETE helps detect misconfigured or vulnerable web servers.

Example command:

nmap --script http-methods -p 80

Reference – CEH v13 Official Study Guide:

Module 11: Hacking Web Applications

Quote:

“The Nmap script http-methods helps identify enabled HTTP methods including potentially dangerous ones like PUT and DELETE.”

Incorrect Options Explained:

B. http-enum is used to enumerate directories and applications, not methods.

C. http-headers retrieves HTTP headers.

D. http-git checks for Git repositories on web servers.

===========

Cloud-based antivirus relies on data collected from endpoint devices and sends that data to cloud servers for real-time malware analysis. This allows rapid updates and detection of new threats without waiting for local signature updates.

???? Reference – CEH v13 Official Study Guide, Module 20: Cryptography and Malware

“Cloud-based detection systems analyze suspicious files and behaviors in the provider’s environment, enabling faster response and reduced endpoint resource usage.”

? Incorrect options:

A. Behavioral-based detection monitors live activity locally.

B. Heuristic-based detection uses rules or behavior patterns locally.

C. Honeypots are decoys for detecting attackers, not antivirus methods.

The scenario describes a hybrid encryption solution based on the OpenPGP standard that uses both symmetric and asymmetric encryption. The key phrase in the question is “a free implementation of the OpenPGP standard,” which directly refers to GPG.

GPG (GNU Privacy Guard) is a free, open-source implementation of the OpenPGP standard.

It combines symmetric encryption for data encryption (fast and efficient) and asymmetric encryption for secure key exchange (using public/private key pairs).

GPG is widely used to secure emails, files, and messages, often in conjunction with tools like Thunderbird or command-line utilities.

Incorrect Options:

A. PGP (Pretty Good Privacy) is the original proprietary implementation of OpenPGP, not free/open-source by default.

B. S/MIME (Secure/Multipurpose Internet Mail Extensions) is another email encryption standard but does not implement OpenPGP.

C. SMTP (Simple Mail Transfer Protocol) is a mail transport protocol, not an encryption method.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Hybrid Encryption and Email Encryption Tools”

Subsection: “GPG and OpenPGP-Based Encryption”

===========

A stealth virus may be a sort of virus malware that contains sophisticated means of avoiding detection by antivirus software. After it manages to urge into the now-infected machine a stealth viruses hides itself by continually renaming and moving itself round the disc.

Like other viruses, a stealth virus can take hold of the many parts of one’s PC. When taking control of the PC and performing tasks, antivirus programs can detect it, but a stealth virus sees that coming and can rename then copy itself to a special drive or area on the disc, before the antivirus software. Once moved and renamed a stealth virus will usually replace the detected ‘infected’ file with a clean file that doesn’t trigger anti-virus detection. It’s a never-ending game of cat and mouse.

The intelligent architecture of this sort of virus about guarantees it’s impossible to completely rid oneself of it once infected. One would need to completely wipe the pc and rebuild it from scratch to completely eradicate the presence of a stealth virus. Using regularly-updated antivirus software can reduce risk, but, as we all know, antivirus software is additionally caught in an endless cycle of finding new threats and protecting against them.

https://www.techslang.com/definition/what-is-a-stealth-virus/

A digital certificate, issued by a trusted Certificate Authority (CA), binds a public key to the identity of an entity (e.g., user, organization). This provides a means to validate ownership of the public key.

CEH v13 Reference:

Module 17: Cryptography

"A digital certificate ensures the authenticity of the public key through a trusted third party known as a Certificate Authority."

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ESP (Encapsulating Security Payload) in transport mode is used for end-to-end communication between hosts within the same LAN. It encrypts only the payload, not the header, ensuring confidentiality and integrity while maintaining efficient routing.

Reference – CEH v13 Official Study Guide:

Module 20: Cryptography

Quote:

“In ESP transport mode, only the data payload is encrypted, making it ideal for secure communication within a LAN where the IP header must remain intact for routing.”

Incorrect Options Explained:

B & C. Not valid IPSec modes.

D. AH tunnel mode ensures integrity but does not provide encryption.

===========

The SSID (service set identifier) is the name of your wireless network. SSID broadcast is how your router transmits this name to surrounding devices. Its primary function is to make your network visible and easily accessible. Most routers broadcast their SSIDs automatically. To disable or enable SSID broadcast, you need to change your router’s settings.

Disabling SSID broadcast will make your Wi-FI network name invisible to other users. However, this only hides the name, not the network itself. You cannot disguise the router's activity, so hackers can still attack it.

With your network invisible to wireless devices, connecting becomes a bit more complicated. Just giving a Wi-FI password to your guests is no longer enough. They have to configure their settings manually by including the network name, security mode, and other relevant info.

Disabling SSID might be a small step towards online security, but by no means should it be your final one. Before considering it as a security measure, consider the following aspects:

- Disabling SSID broadcast will not hide your network completely

Disabling SSID broadcast only hides the network name, not the fact that it exists. Your router constantly transmits so-called beacon frames to announce the presence of a wireless network. They contain essential information about the network and help the device connect.

- Third-party software can easily trace a hidden network

Programs such as NetStumbler or Kismet can easily locate hidden networks. You can try using them yourself to see how easy it is to find available networks – hidden or not.

- You might attract unwanted attention.

Disabling your SSID broadcast could also raise suspicion. Most of us assume that when somebody hides something, they have a reason to do so. Thus, some hackers might be attracted to your network.

Password cracking is a core component of the system hacking phase. CEH materials highlight that once password hashes are obtained, attackers often perform offline cracking to avoid detection and bypass account lockout policies. Tools like Hashcat make use of hardware acceleration—specifically, GPU or multi-core CPU computing—to significantly increase cracking throughput. Hardware acceleration allows the system to perform thousands to millions of hash calculations simultaneously, dramatically improving cracking efficiency compared to traditional CPU-bound methods. While dumping SAM contents is part of credential extraction, it is not the optimization described in the scenario. Dictionary rules influence cracking strategy but not raw speed. NetBIOS spoofing is unrelated to password cracking. The emphasis here is on maximizing computational power to accelerate the hash-cracking process, aligning directly with CEH’s explanation of hardware-accelerated offline cracking techniques.

ARIN (American Registry for Internet Numbers) is a Regional Internet Registry (RIR) that provides information about IP address allocations and autonomous systems in North America. It’s used for WHOIS lookups and footprinting in reconnaissance.

The AndroidManifest.xml file contains information of your package, including components of the appliance like activities, services, broadcast receivers, content providers etc.

It performs another tasks also:

• it’s responsible to guard the appliance to access any protected parts by providing the permissions.

• It also declares the android api that the appliance goes to use.

• It lists the instrumentation classes. The instrumentation classes provides profiling and other informations. These informations are removed just before the appliance is published etc.

This is the specified xml file for all the android application and located inside the basis directory.

The base metric represents the inherent qualities of a vulnerability, according to the Common Vulnerability Scoring System (CVSS). CVSS is a framework that numerically characterizes the severity of software vulnerabilities between the range of 0-10. CVSS consists of three metric groups: Base, Temporal, and Environmental. The base metric group captures the characteristics of a vulnerability that are constant over time and across user environments. The base metric group consists of six sub-metrics: Attack Vector, Attack Complexity, Privileges Required, User Interaction, Scope, and Impact. The impact sub-metric further consists of three sub-metrics: Confidentiality, Integrity, and Availability. The base metric group produces a score ranging from 0 to 10, which reflects the intrinsic and fundamental properties of a vulnerability12.

The other options are not correct for the following reasons:

A. Temporal metric represents the inherent qualities of a vulnerability: This option is incorrect because the temporal metric group captures the characteristics of a vulnerability that change over time due to events external to the vulnerability. The temporal metric group consists of three sub-metrics: Exploit Code Maturity, Remediation Level, and Report Confidence. The temporal metric group modifies the base score to reflect the current state of the vulnerability, such as the availability of exploit code, the existence of patches or workarounds, and the degree of verification of the vulnerability report12.

C. Environmental metric involves the features that change during the lifetime of the vulnerability: This option is incorrect because the environmental metric group captures the characteristics of a vulnerability that are relevant and unique to a user’s environment. The environmental metric group consists of three sub-metrics: Modified Attack Vector, Modified Attack Complexity, and Modified Privileges Required. The environmental metric group also allows the user to assign importance values to the impact sub-metrics: Confidentiality Requirement, Integrity Requirement, and Availability Requirement. The environmental metric group modifies the base and temporal scores to reflect the impact of the vulnerability on the user’s specific environment, such as the network configuration, the security objectives, and the asset value12.

D. Temporal metric involves measuring vulnerabilities based on a specific environment or implementation: This option is incorrect because the temporal metric group does not involve measuring vulnerabilities based on a specific environment or implementation, but rather on the factors that change over time due to events external to the vulnerability. The environmental metric group, not the temporal metric group, involves measuring vulnerabilities based on a specific environment or implementation, as explained in option C.

Infoga may be a tool gathering email accounts informations (ip,hostname,country,…) from completely different public supply (search engines, pgp key servers and shodan) and check if email was leaked using haveibeenpwned.com API. is a really simple tool, however very effective for the first stages of a penetration test or just to know the visibility of your company within the net.

Passive reconnaissance focuses on collecting intelligence without interacting with the target's systems. CEH materials emphasize reviewing publicly available information, including leaked documents, breach data, reports, or exposed metadata, as this yields internal network structure details while generating no detectable traffic. This method avoids triggering monitoring systems and aligns with stealth requirements for covert intelligence gathering.

Sniffing attacks are a type of network attack that involves intercepting and analyzing data packets as they travel over a network. Sniffing attacks can be used to steal sensitive information, such as usernames, passwords, credit card numbers, etc. Sniffing attacks can also be used to perform reconnaissance, spoofing, or man-in-the-middle attacks.

The IT department of the company has implemented some security measures to prevent or mitigate sniffing attacks, such as:

Adding the MAC address of the gateway to the ARP cache: This prevents ARP spoofing, which is a technique that allows an attacker to redirect network traffic to their own device by sending fake ARP messages that associate their MAC address with the IP address of the gateway.

Switching to IPv6 instead of IPv4: This reduces the risk of IP spoofing, which is a technique that allows an attacker to send packets with a forged source IP address, pretending to be another device on the network.

Using encrypted sessions such as SSH instead of Telnet, and Secure File Transfer Protocol instead of FTP: This protects the data from being read or modified by an attacker who can capture the packets, as the data is encrypted and authenticated using cryptographic protocols.

However, these measures are not enough to completely eliminate the threat of sniffing, as an attacker can still use other techniques, such as:

Passive sniffing: This involves monitoring the network traffic without injecting any packets or altering the data. Passive sniffing can be done on a shared network, such as a hub, or on a switched network, using techniques such as MAC flooding, port mirroring, or VLAN hopping.

Active sniffing: This involves injecting packets or modifying the data to manipulate the network behavior or gain access to more traffic. Active sniffing can be done using techniques such as DHCP spoofing, DNS poisoning, ICMP redirection, or TCP session hijacking.

Therefore, the next step to enhance network security is to implement network scanning and monitoring tools, which can help detect and prevent sniffing attacks by:

Scanning the network for unauthorized devices, such as rogue access points, hubs, or sniffers, and removing them or isolating them from the network.

Monitoring the network for abnormal traffic patterns, such as excessive ARP requests, DNS queries, ICMP messages, or TCP connections, and alerting the network administrators or blocking the suspicious sources.

Analyzing the network traffic for malicious content, such as malware, phishing, or exfiltration, and filtering or quarantining the infected or compromised devices.

Before enforcing policies or issuing warnings, the most effective first step is to educate employees. Awareness training helps build a foundational understanding of risks and best practices, especially in low-security cultures.

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CEH v13 explains that Windows systems running older or default configurations often allow anonymous or null session connections to IPC$ shares, enabling attackers to enumerate users, groups, shares, and other system details without authentication. Null session enumeration is highlighted as a classic yet effective technique because it generates minimal detectable activity and does not require credentials, making it ideal for stealth operations. CEH stresses that SMB null sessions are frequently overlooked in legacy or poorly hardened environments, especially when default permissions remain unchanged. Packet sniffing (Option A) may provide some data but requires traffic visibility and may be detected through monitoring tools. DNS zone transfers (Option B) require misconfigurations and usually do not reveal user list details. SNMP queries (Option D) require community strings and often generate alerts. Therefore, exploiting null sessions is the most covert and effective method for enumerating Windows systems under default configurations.

In CEH v13 Module 01: Introduction to Ethical Hacking, Business Impact Analysis (BIA) is defined as a core component of the risk management process that helps identify and evaluate critical business functions, their dependencies, and the impact of downtime.

BIA is performed to:

Identify critical services and resources.

Determine the impact of their failure.

Define Recovery Time Objectives (RTO) and Recovery Point Objectives (RPO).

Prioritize systems for business continuity planning.

Option Clarification:

A. EPR: Emergency Plan Response – not a formal phase in BIA or risk analysis.

C. Risk Mitigation: Involves taking actions to reduce risks, but doesn't identify business-critical services.

D. DRP: Disaster Recovery Planning focuses on restoration, not impact assessment.

Spanning Tree Protocol (STP) manipulation attacks involve an attacker injecting BPDUs (Bridge Protocol Data Units) to force a switch to recognize the attacker’s system as the root bridge. Once this is achieved, the attacker can:

Redirect traffic through their own machine

Create a SPAN (Switched Port Analyzer) session to mirror traffic

Intercept, sniff, or modify data passing through the network

This is typically the next logical step in an STP attack to facilitate a Man-in-the-Middle (MITM) position.

Reference – CEH v13 Official Study Guide:

Module 8: Sniffing

Quote:

“An attacker who becomes the root bridge using STP manipulation can redirect traffic and use SPAN ports to mirror traffic to their system for analysis or manipulation.”

Incorrect Options:

B. OSPF is a Layer 3 routing protocol, not relevant here.

C. DoS is not the goal of this specific attack.

D. Attacking all switches is inefficient and unnecessary once root access is gained.

===========

According to CEH v13 Module 06: Malware Threats, USB Dumper is a tool often used in insider threat or data exfiltration scenarios, where it automatically and silently copies files from any USB drive connected to a system.

It operates in the background and requires no user interaction once installed.

Files are copied from the USB to a pre-configured local directory.

USB Dumper is used in various penetration testing scenarios to simulate data theft using physical access.

Option Clarifications:

A. USB Grabber: Not a recognized standard tool in CEH or industry.

B. USB Snoopy: Used for monitoring USB communications (not silent copying).

C. USB Sniffer: Used for sniffing USB device communication traffic, not file theft.

D. USB Dumper: Correct tool for silently copying USB content.

Comprehensive and Detailed Explanation:

Cryptographic hash functions provide:

Integrity: Any change in the input changes the output hash.

Collision Resistance: It is computationally infeasible to find two inputs that produce the same hash.

This ensures data is not altered during transmission.

From CEH v13 Courseware:

Module 10: Cryptography ? Hashing Functions (e.g., SHA-256, MD5)

There is no single, standardized classification of cross-site scripting flaws, but most experts distinguish between at least two primary flavors of XSS flaws: non-persistent and persistent. In this issue, we consider the non-persistent cross-site scripting vulnerability.

The non-persistent (or reflected) cross-site scripting vulnerability is by far the most basic type of web vulnerability. These holes show up when the data provided by a web client, most commonly in HTTP query parameters (e.g. HTML form submission), is used immediately by server-side scripts to parse and display a page of results for and to that user, without properly sanitizing the content.

Because HTML documents have a flat, serial structure that mixes control statements, formatting, and the actual content, any non-validated user-supplied data included in the resulting page without proper HTML encoding, may lead to markup injection. A classic example of a potential vector is a site search engine: if one searches for a string, the search string will typically be redisplayed verbatim on the result page to indicate what was searched for. If this response does not properly escape or reject HTML control characters, a cross-site scripting flaw will ensue.

Non-repudiation is the assurance that someone cannot deny the validity of something. Non-repudiation is a legal concept that is widely used in information security and refers to a service, which provides proof of the origin of data and the integrity of the data. In other words, non-repudiation makes it very difficult to successfully deny who/where a message came from as well as the authenticity and integrity of that message.

CEH describes SQL injection testing as a core part of web application assessment. One of the first and safest validation techniques is using a tautology-based SQL injection payload, such as ' OR '1'='1. If the application concatenates user input directly into SQL queries, such an input will cause the query to always evaluate as true, often returning additional records such as multiple user profiles. This confirms the presence of SQL injection without causing destructive effects like dropping tables. Testing XSS does not validate SQL injection, brute-forcing credentials is unrelated, and directory traversal attacks target file path manipulation rather than backend queries. CEH emphasizes avoiding destructive queries and starting with non-intrusive injection payloads that reveal improper input sanitization, making ' OR '1'='1 the correct technique for confirming SQL injection vulnerabilities in URL parameters.

The main purpose of a rootkit is to hide malicious activity by modifying or replacing legitimate system binaries (e.g., ls, ps, netstat) so they no longer show the presence of malicious files, users, or processes. This enables attackers to maintain persistent and stealthy access.

From CEH v13 Official Courseware:

Module 6: Malware Threats ? Rootkits

CEH v13 Study Guide states:

“Rootkits are stealthy programs designed to conceal the existence of other malicious processes or programs by replacing legitimate operating system utilities and binaries. This makes detection and removal extremely difficult.”

Incorrect Options:

A: This is a backdoor’s behavior.

B: A buffer overflow is a method of exploitation, not the rootkit’s purpose.

D: Refers to a backdoor or vulnerability, not a rootkit’s core function.

CSRF occurs when a vulnerable application processes unauthorized state-changing requests because it does not verify whether the request was intentionally initiated by the authenticated user. CEH v13 explains that exploitation involves tricking a logged-in user into unknowingly executing a crafted HTTP request—usually via a malicious webpage, hidden form submission, embedded image tag, or JavaScript trigger. When the victim visits the attacker-controlled page, the browser automatically includes the user’s active session cookies, allowing the server to treat the forged request as legitimate. This technique is central to CSRF attacks and is highlighted in the CEH curriculum as the correct exploitation path. Directory traversal, SQL injection, and brute-force attacks target different vulnerabilities and do not exploit missing request authenticity validation. The key requirement for CSRF exploitation is user interaction via a malicious external resource, making option B the correct CEH-aligned method.

-A: Perform an aggressive scan which select most of the commonly used options within nmap

-Pn: Means Don't ping

-p:scan specific ports

-sT: TCP Connect scan

-O: Operating system detection

-T0: timing template (extremely slow- evade FW)0

The scenario describes an injection attack involving Server Side Includes (SSI). SSI directives are instructions placed in web pages that are executed by the web server before the page is sent to the user. If user input is improperly validated and directly used in an SSI-enabled environment, attackers can inject malicious SSI directives (such as file manipulation commands).

From CEH v13 Official Courseware:

Server-Side Includes (SSI) Injection occurs when attackers submit specially crafted input that is included in server responses and interpreted as SSI directives.

These directives can perform dangerous actions like:

Reading sensitive files (e.g., /etc/passwd)

Deleting or modifying files

Running shell commands via #exec directive

Incorrect options:

A. Server-side template injection is related to template engines like Jinja2 or Twig.

B. Server-side JS injection applies to environments like Node.js.

C. CRLF injection manipulates HTTP headers, not SSI parsing.

Reference – CEH v13 Official Courseware:

Module 14: Hacking Web Applications

Section: “Injection Flaws”

Subsection: “SSI Injection”

Lab Reference: CEH iLabs – Web Application Exploitation

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Regional Internet Registries (RIRs):

ARIN (American Registry for Internet Numbers)

AFRINIC (African Network Information Center)

APNIC (Asia Pacific Network Information Center)

RIPE (Réseaux IP Européens Network Coordination Centre)

LACNIC (Latin American and Caribbean Network Information Center)

MX (Mail Exchange) records in DNS define the mail servers responsible for receiving email for a domain. Each MX record has a priority value.

Important concept:

A lower number indicates a higher priority.

Email servers attempt delivery to the mail server with the lowest priority first.

For example:

If MX records are:

10 mail1.example.com

20 mail2.example.com

Then mail1 will be tried first. If it fails, mail2 will be used.

So the statement “MX record priority increases as the number increases” is false.

In CEH v13 Module 10 & 12: Vulnerability Analysis and Web Hacking, Netsparker is introduced as a leading automated web vulnerability scanner capable of detecting:

SQL Injection

Cross-site Scripting (XSS)

Local File Inclusion (LFI)

Misconfigured services

Authentication issues

It performs:

Crawling, attack simulation, and detailed reporting.

Ideal for automated assessment of web servers and applications.

Option Clarification:

A. Infoga: Email information gathering tool.

B. WebCopier Pro: Used for offline website downloading.

C. Netsparker: Purpose-built web vulnerability scanner.

D. NCollector Studio: Website archiving tool, not vulnerability-focused.

18 U.S.C. §1030, also known as the Computer Fraud and Abuse Act (CFAA), is a broad federal statute that criminalizes unauthorized access to computers and related fraudulent activities—including phishing and email scams.

From CEH v13 Official Courseware:

Module 1: Introduction to Ethical Hacking

Topic: U.S. Laws Related to Cybercrime

CEH v13 Study Guide states:

“Email-based frauds such as phishing, spoofing, and other social engineering attacks fall under the Computer Fraud and Abuse Act (18 U.S.C. §1030), which criminalizes unauthorized access and fraudulent behavior in computing systems.”

Incorrect Options:

B: Relates to credit cards and access devices.

C: Covers interference with government communication systems.

D: Covers illegal wiretapping and eavesdropping.

In CEH v13 Module 11: Hacking Wireless Networks, WPA3 is presented as the latest Wi-Fi security protocol, and it includes:

Simultaneous Authentication of Equals (SAE) protocol — a more secure key exchange mechanism.

Replaces WPA2's Pre-Shared Key (PSK) method to prevent dictionary and key recovery attacks.

SAE (a.k.a. Dragonfly) prevents attackers from capturing handshakes for offline cracking.

Option Clarification:

A. WEP: Obsolete and weak.

B. WPA: Early improvement over WEP, still vulnerable.

C. WPA2: Uses PSK and vulnerable to key reinstallation attacks (KRACK).

D. WPA3: Correct – uses SAE/Dragonfly, resistant to known attacks.

The most effective attack method for the penetration tester to exploit these vulnerabilities and attempt unauthorized access would be to execute a Brute Force attack, leveraging the lack of account lockout policy and the verbose error messages to guess the correct credentials. A Brute Force attack is a hacking method that uses trial and error to crack passwords, login credentials, or encryption keys. It is a simple yet reliable tactic for gaining unauthorized access to individual accounts and organizations’ systems and networks1. In this scenario, the tester can take advantage of the fact that the application does not lock out users after multiple failed login attempts, which means the tester can try as many combinations as possible without being blocked. The tester can also use the detailed error messages that disclose whether the username or password entered is incorrect, which can help narrow down the search space and reduce the number of guesses needed. For example, if the tester enters a wrong username and a wrong password, and the application responds with “Invalid username”, the tester can eliminate that username from the list of candidates and focus on finding the correct one. Similarly, if the tester enters a correct username and a wrong password, and the application responds with “Invalid password”, the tester can confirm that username and focus on finding the correct password. By using automated tools or scripts, the tester can perform a Brute Force attack faster and more efficiently.

The other options are not as effective or feasible as option A for the following reasons:

B. The tester could exploit a potential SQL Injection vulnerability to manipulate the application’s database: This option is not feasible because there is no indication that the application is vulnerable to SQL Injection, which is a web security vulnerability that allows an attacker to interfere with the queries that an application makes to its database2. The application uses form-based authentication, which does not necessarily involve SQL queries, and the error messages do not reveal any SQL syntax or structure. Moreover, even if the application was vulnerable to SQL Injection, the tester would need to craft a malicious SQL query that can bypass the authentication mechanism and grant access to the application, which may not be possible or easy depending on the database design and configuration.

C. The tester could launch a Cross-Site Scripting (XSS) attack to steal authenticated session cookies, potentially bypassing the clickjacking protection: This option is not effective because there is no evidence that the application is vulnerable to XSS, which is a web security vulnerability that allows an attacker to compromise the interactions that users have with a vulnerable application by injecting malicious scripts3. The application uses HTTP headers to prevent clickjacking attacks, which are a type of attack that tricks a user into clicking on a hidden or disguised element on a web page4. However, this does not imply that the application is vulnerable to XSS, which requires a different type of injection point and payload. Moreover, even if the application was vulnerable to XSS, the tester would need to find a way to deliver the malicious script to a legitimate user who is already authenticated, and then capture the stolen session cookies from the user’s browser, which may not be feasible or easy depending on the application’s design and security measures.

D. The tester could execute a Man-in-the-Middle (MitM) attack to intercept and modify the HTTP headers for a Clickjacking attack: This option is not feasible because a MitM attack is a type of attack that requires the attacker to insert themselves between two parties who believe that they are directly communicating with each other, and then relay or alter the communications between them5. In this scenario, the tester would need to intercept the HTTP traffic between the user and the application, and then modify the HTTP headers to remove or weaken the clickjacking protection. However, this would require the tester to have access to the network infrastructure or the user’s device, which may not be possible or easy depending on the network security and encryption. Moreover, even if the tester could perform a MitM attack, the tester would still need to trick the user into clicking on a malicious element on a web page, which may not be possible or easy depending on the user’s awareness and behavior.

The TTL (Time-To-Live) and TCP window size are commonly used values for passive OS fingerprinting. Different operating systems set default values for these fields in IP and TCP headers.

From CEH v13 Official Courseware and tools like Nmap and Netcraft:

A TTL of 64 and TCP window size of 5840 is a strong indicator of a Linux-based operating system.

This combination is one of the signature responses used in tools such as Nmap and p0f to fingerprint OS remotely.

Here’s a general reference table:

OS

Default TTL

TCP Window Size

Windows

128

8192/65535

Linux

64

5840

Solaris

255

8760

Mac OS

64

65535

Therefore, TTL: 64 + Window Size: 5840 = Linux OS

Incorrect Options:

A. Solaris typically has a TTL of 255 and a different window size.

B. Windows defaults to TTL 128.

C. Mac OS uses TTL 64 but has a window size of 65535.

Reference – CEH v13 Official Courseware:

Module 03: Scanning Networks

Section: “OS Detection Using TTL and TCP Window Size”

Tools: Nmap OS Fingerprinting, Xprobe2

CEH iLab: OS Fingerprinting with TCP/IP Stack Behavior

===========

The ethical hacker conducted Test 1, which is a TCP/IP stack fingerprinting technique that uses the SYN and ECN-Echo flags to determine the OS of the target system. The SYN flag is used to initiate a TCP connection, and the ECN-Echo flag is used to indicate that the sender supports Explicit Congestion Notification (ECN), which is a mechanism to reduce network congestion. Different OSes have different implementations and responses to these flags, which can reveal their identity. For example, Windows XP and 2000 will reply with SYN and ECN-Echo flags set, while Linux will reply with only SYN flag set. By sending a TCP packet with these flags enabled to an open TCP port and observing the reply, the ethical hacker can probe the nature of the response and subsequently determine the OS fingerprint.

The ethical hacker adopted this specific approach because it is an advanced and stealthy technique that can evade some firewalls and intrusion detection systems (IDS) that may block or alert other types of packets, such as NULL, FIN, or Xmas packets. Moreover, this technique can provide more accurate and reliable results than other techniques, such as banner grabbing or passive analysis, that may depend on the availability or validity of the information provided by the target system.

The other options are not correct, as they describe different tests and reasons. Test 3 is a TCP/IP stack fingerprinting technique that uses the URG, PSH, SYN, and FIN flags to determine the OS of the target system. Test 2 is a TCP/IP stack fingerprinting technique that uses a NULL packet, which is a TCP packet with no flags enabled, to determine the OS of the target system. Test 6 is a TCP/IP stack fingerprinting technique that uses the ACK flag, which is used to acknowledge the receipt of a TCP segment, to determine the OS of the target system. References:

OS and Application Fingerprinting | SANS Institute

Operating System Fingerprinting | SpringerLink

OS and Application Fingerprinting - community.akamai.com

What is OS Fingerprinting and Techniques - Zerosuniverse

The virus described changes its own code with each execution but still performs the same actions. This is the hallmark of a Metamorphic Virus. Unlike polymorphic viruses (which use encrypted code with a changing decryptor), metamorphic viruses rewrite their own code entirely — including their decryption and execution routines — to avoid pattern detection by antivirus software.

Key characteristics of metamorphic viruses seen in the scenario:

Mutates completely on every execution.

Keeps overall functionality identical (semantics intact).

Alters its appearance and logic flow.

From CEH v13 Courseware:

Module 6: Malware Threats ? Types of Viruses and Obfuscation Techniques

CEH v13 Study Guide states:

“Metamorphic viruses modify their own code structure and appearance with each iteration, without altering their underlying behavior. This makes them more difficult to detect through signature-based mechanisms.”

Incorrect Options:

A: Polymorphic viruses encrypt themselves with a changing decryptor stub but do not change their core logic.

C: “Dravidic Virus” is not a recognized term in cybersecurity.

D: Stealth viruses hide their presence (e.g., by intercepting system calls), but do not change their code structure.

Comprehensive and Detailed Explanation From CEH v13 Guide:

R-U-Dead-Yet? (RUDY) is a DoS tool that targets web applications by sending slow HTTP POST requests with large Content-Length headers. This consumes server resources, leading to a denial of service.

CEH v13 Reference:

Module 9: Denial-of-Service – DoS Tools

“R-U-Dead-Yet? (RUDY) sends long-form POST requests to consume server-side sessions and exhaust resources without completing the transaction.”

This scenario demonstrates a classic social engineering tactic often referred to as “social media quizzes” or “engagement bait”, commonly used in open-source intelligence gathering (OSINT) and pretexting attacks.

From CEH v13 Module 01: Introduction to Ethical Hacking and Module 09: Social Engineering, attackers may create seemingly innocent posts that ask users to share answers to common questions like:

What was your first pet’s name?

What’s your mother’s maiden name?

What city were you born in?

What’s your favorite food?

These questions mirror the types of security questions used by banks and other services for account recovery or authentication. By answering these in public forums or comments, users unknowingly disclose data that can be used to:

Bypass security questions

Reset passwords

Perform targeted account takeovers

Why Other Options Are Incorrect:

B. Matt's bank account login information was brute forced.

Unlikely. Most banks implement account lockout policies and multi-factor authentication that would prevent brute force attempts.

C. Matt inadvertently provided his password when responding to the post.

Incorrect. Passwords are not usually asked in public-facing posts. Users are unlikely to provide literal passwords unless heavily tricked by phishing.

D. Matt's computer was infected with a keylogger.

Possible but less likely. The context suggests that the only suspicious behavior was responding to the Facebook post, which doesn't imply malware installation or downloading.

Reference from CEH v13 Study Guide and Course Material:

CEH v13 Official Module 09 – Social Engineering, Slide: Common Social Engineering Techniques (Quizzes, Pretexting)

CEH Engage – Social Engineering Phase

EC-Council iLabs – Performing Social Engineering Attacks Simulation

CEH v13 Courseware Notes – Reconnaissance Using OSINT and Public Social Platforms

A multihomed firewall refers to a firewall with two or more network interfaces (NICs), each connected to different network segments. The purpose of a multihomed firewall is to allow filtering and segmentation of traffic between multiple network zones, such as:

External network (e.g., Internet)

Internal network (e.g., LAN)

To qualify as multihomed, the system must have at least two network interfaces. This allows it to sit between two networks and inspect/filter traffic passing through it.

Reference – CEH v13 Official Study Guide:

Module 13: Evading IDS, Firewalls, and Honeypots

Section: Firewall Architecture

Quote:

“A multihomed firewall is a system with two or more NICs connected to different networks, typically used to control traffic between internal and external networks. The minimum number of interfaces is two.”

Incorrect Options Explained:

A. 3 interfaces may be used in advanced setups (e.g., with a DMZ), but not the minimum.

B & C. 4 or 5 connections are not required unless designing more complex segmentation.

===========

CEH v13 teaches that NetBIOS enumeration is a key technique for gathering information in Windows environments without raising alarms. Ports 137 and 139 indicate that NetBIOS Name Service (NBNS) and SMB services are active. The tool nbtstat -A <IP> retrieves valuable information including computer names, logged-in users, domain/workgroup membership, and system roles—all passively and without authentication. CEH emphasizes that querying NetBIOS is often overlooked by defenders and generates minimal noise, making it ideal for stealth enumeration. LDAP enumeration (Option A) requires directory access and tends to trigger logs. Psloggedon and pspasswd (Options B and D) involve active interaction and authentication attempts, which are far more detectable. nbtstat is the CEH-recommended tool for initial reconnaissance on Windows networks using NetBIOS and SMB, especially when quiet enumeration is required.

When a NULL scan is sent to a port on a UNIX-based system:

If the port is OPEN: The system does not respond at all.

If the port is CLOSED: The system responds with a RST packet.

This behavior is based on how the TCP stack processes unexpected packets.

From CEH v13 Courseware:

Module 3: Scanning Networks

Topic: Stealth Scanning Techniques ? NULL Scan

CEH v13 Official Guide states:

“A NULL scan sends a TCP packet with no flags set. On systems following RFC 793 (like many Unix/Linux), open ports silently drop such packets (no response), while closed ports respond with a TCP RST.”

Incorrect Options:

A–E: Not standard responses for an open port in a NULL scan scenario.

In CEH v13 Module 14: Cryptography, IPSec (Internet Protocol Security) is defined as a framework used to establish secure communication channels over IP networks, particularly in VPNs.

IPSec supports encryption, authentication, and integrity.

Operates in Tunnel Mode (VPNs) or Transport Mode (End-to-End).

Core protocols: AH (Authentication Header) and ESP (Encapsulating Security Payload).

Option Analysis:

A. PEM: Privacy Enhanced Mail (email encryption).

B. PPP: Point-to-Point Protocol (data link layer, not encryption).

C. IPSEC: VPN encryption protocol.

D. SET: Secure Electronic Transaction (used in payment systems, obsolete).

SMTP enumeration involves probing a mail server to gather information about users and configurations. Two important SMTP commands used in enumeration are:

VRFY: Verifies whether a particular email address or user ID exists on the mail server.

EXPN: Reveals the actual addresses behind a mailing list or alias.

These commands allow attackers or penetration testers to enumerate valid user accounts or group memberships, which can later be targeted for phishing, spam, or brute-force attacks.

Incorrect Options:

B. Daily outgoing message limits are not typically disclosed via SMTP.

C. RCPT TO is used to designate a message recipient, but it doesn't enumerate open ports.

D. Mail proxy addresses are not revealed directly via SMTP enumeration.

Reference – CEH v13 Official Courseware:

Module 04: Enumeration

Section: “SMTP Enumeration Techniques”

Tool Reference: smtp-user-enum, Netcat

===========

According to CEH v13 Module 03: Scanning Networks, when using Nmap for service enumeration and fingerprinting, the flag to determine service version and type information is:

-sV — Version Detection Scan

nmap -sV instructs Nmap to actively connect to open ports and probe the services running on those ports. This technique helps identify:

The service name (e.g., Apache, Nginx, etc.)

The version number (e.g., Apache 2.4.54)

The OS or device details (when possible)

This is especially useful when ports like 80 (HTTP) and 443 (HTTPS) are open, as it helps determine which web server is running (e.g., Apache, IIS, Nginx) and its version — which is critical for vulnerability assessment.

Why Other Options Are Incorrect:

A. -sv

? Incorrect syntax. Nmap flags are case-sensitive and this is a typo. Correct flag is -sV.

B. -Pn

Skips host discovery (ping scan). It does not provide service version info.

C. -V

Displays Nmap’s version, not the service version on the target.

D. -ss

Incorrect spelling. You may have meant -sS (TCP SYN scan), which is for port scanning, not version detection.

Correct Option is A, assuming the intent is to write the correct syntax as -sV. However, strictly speaking, if this is a case-sensitive exam, and the listed option is -sv (lowercase 'v'), it would be invalid. But based on CEH exam context where minor casing issues are accepted if conceptually correct, A is the best answer.

Reference from CEH v13 Study Guide and Courseware:

Module 03 – Scanning Networks, Section: Nmap Scan Types and Options

EC-Council iLabs: Performing Version Detection Using nmap -sV

Nmap Official Docs (Referenced in CEH): https://nmap.org/book/man-version-detection.html

-h | findstr " -sV" -sV: Probe open ports to determine service/version info

This is a classic example of Web Parameter Tampering. This occurs when attackers manipulate parameters exchanged between client and server to exploit vulnerabilities in the application logic. In this case:

Damount and Camount are passed via URL parameters.

The web application is not validating or sanitizing the values.

Altering the values affects the transaction outcome.

This is not an SQL Injection (no SQL code shown), nor is it XSS (no script injection), and it is unrelated to Cookie Tampering (which involves browser-stored cookies).

White-box testing (also known as clear box testing, glass box testing, transparent box testing, and structural testing) is a method of software testing that tests internal structures or workings of an application, as opposed to its functionality (i.e. black-box testing). In white-box testing, an internal perspective of the system, as well as programming skills, are used to design test cases. The tester chooses inputs to exercise paths through the code and determine the expected outputs. This is analogous to testing nodes in a circuit, e.g. in-circuit testing (ICT). White-box testing can be applied at the unit, integration and system levels of the software testing process. Although traditional testers tended to think of white-box testing as being done at the unit level, it is used for integration and system testing more frequently today. It can test paths within a unit, paths between units during integration, and between subsystems during a system-level test. Though this method of test design can uncover many errors or problems, it has the potential to miss unimplemented parts of the specification or missing requirements. Where white-box testing is design-driven,[1] that is, driven exclusively by agreed specifications of how each component of the software is required to behave (as in DO-178C and ISO 26262 processes) then white-box test techniques can accomplish assessment for unimplemented or missing requirements.

White-box test design techniques include the following code coverage criteria:

· Control flow testing

· Data flow testing

· Branch testing

· Statement coverage

· Decision coverage

· Modified condition/decision coverage

· Prime path testing

· Path testing

· Identifying operating systems, services, protocols and devices,

· Collecting unencrypted information about usernames and passwords,

· Capturing network traffic for further analysis

are passive network sniffing methods since with the help of them we only receive information and do not make any changes to the target network. When modifying and replaying the captured network traffic, we are already starting to make changes and actively interact with it.

CEH’s social engineering principles highlight psychological manipulation techniques such as authority, urgency, trust exploitation, and impersonation. In this scenario, the attacker leverages “perceived authority,” a powerful influence tactic where the social engineer poses as someone with legitimate power or sanctioned access—such as a technician, auditor, or vendor representative. CEH emphasizes that referencing real employee names, using technical terminology, and impersonating trusted third-party partners increases believability and reduces verification resistance. The receptionist’s acceptance of the attacker’s presence without verifying credentials matches classical authority-based exploitation. Leaked credentials, physical security logs, and network segmentation issues do not relate to human-layer social engineering. The situation clearly reflects the manipulation of trust and authority as described in CEH’s psychological attack vectors.

In CEH v13 Module 11: Hacking Wireless Networks, Kismet is introduced as a passive wireless sniffer and network detector used primarily on Linux systems.

Kismet passively listens for wireless beacons and data frames.

Can detect hidden SSIDs, rogue APs, and even wireless client behaviors.

Does not transmit any packets, making it stealthy and ideal for wireless reconnaissance.

Option Analysis:

A. Burp Suite: Used for web application testing, not wireless.

B. OpenVAS: Vulnerability scanner, not a packet sniffer.

C. tshark: CLI version of Wireshark, can analyze wired and wireless packets, but not wireless-specific or passive by default.

D. Kismet: Correct wireless packet analyzer for Linux.

In CEH v13 Module 16: Cloud Computing and Container Security, Kubernetes components are explained for understanding container orchestration risks.

Kube-scheduler is the master node component responsible for:

Assigning newly created pods to available nodes.

Evaluating each pod’s resource requirements.

Considering node affinity/anti-affinity, data locality, hardware restrictions, etc.

Ensuring workload balancing across nodes.

Other Options:

A. Kube-controller-manager: Manages control loops for replication and status.

C. Kube-apiserver: Acts as the entry point for all REST commands.

D. Etcd: A key-value store used to save configuration data.

JXplorer could be a cross platform LDAP browser and editor. it’s a standards compliant general purpose LDAP client which will be used to search, scan and edit any commonplace LDAP directory, or any directory service with an LDAP or DSML interface.

It is extremely flexible and can be extended and custom in a very number of the way. JXplorer is written in java, and also the source code and source code build system ar obtainable via svn or as a packaged build for users who wish to experiment or any develop the program.

JX is is available in 2 versions; the free open source version under an OSI Apache two style licence, or within the JXWorkBench Enterprise bundle with inbuilt reporting, administrative and security tools.

JX has been through a number of different versions since its creation in 1999; the foremost recent stable release is version 3.3.1, the August 2013 release.

JXplorer could be a absolutely useful LDAP consumer with advanced security integration and support for the harder and obscure elements of the LDAP protocol. it’s been tested on Windows, Solaris, linux and OSX, packages are obtainable for HPUX, AIX, BSD and it should run on any java supporting OS.

Censys is a powerful Internet-wide scanning tool that allows users to:

Discover and analyze devices and services exposed to the public internet

Enumerate connected IoT devices, open ports, software versions

Provide structured and searchable reports for vulnerability analysis

According to CEH v13:

Censys continuously scans the IPv4 address space and maintains up-to-date databases of connected devices and their metadata.

Incorrect Options:

B. Wapiti is a web application vulnerability scanner.

C. NeuVector is a container security solution.

D. Lacework is a cloud workload protection platform, not focused on IoT enumeration.

Reference – CEH v13 Official Courseware:

Module 18: IoT and OT Hacking

Section: “IoT Discovery Tools”

Tool Focus: Censys, Shodan

===========

CEH v13 highlights the Idle Scan as one of the stealthiest reconnaissance methods available, designed specifically to avoid detection by IDS and security monitoring tools. Idle scanning leverages a “zombie host”—a system with a predictable IPID sequence—to route all probe packets through it. Since no packets ever originate directly from the attacker’s IP, IDS systems are unable to attribute the port scan to the attacker. CEH emphasizes that this technique creates zero direct traffic between the attacker and the target, making it extremely evasive and ideal for highly monitored networks. FIN scans (Option A) are somewhat stealthy but still originate from the attacker and are detectable. TCP Connect scans (Option C) are the most detectable because they complete full connections. ICMP Echo scans (Option D) are easily logged and flagged by IDS. Idle scanning is uniquely suited for bypassing advanced detection systems while still identifying open ports and live hosts.

CEH v13 highlights the importance of route tracing during internal reconnaissance to identify key infrastructure devices such as distribution switches, firewalls, and core routers. When a single IP address consistently appears as the penultimate hop across multiple network paths, this typically indicates that the device serves as a core router responsible for inter-VLAN or inter-subnet routing. Core routers aggregate traffic from various segments before forwarding to endpoint subnets, explaining why it appears before diverse destinations. CEH emphasizes recognizing core infrastructure because compromising such devices provides attackers with significant visibility and potential control over network-wide communications. DNS poisoning would affect name resolution, not hop patterns. Loopback misconfigurations would affect single hosts, not multiple segments. A transparent proxy would appear only for traffic routed through application-layer inspection, not all traceroute tests. The consistency across subnets strongly points to a centralized routing device.

PHI stands for Protected Health info. The HIPAA Privacy Rule provides federal protections for private health info held by lined entities and provides patients an array of rights with regard to that info. under HIPAA phi is considered to be any identifiable health info that’s used, maintained, stored, or transmitted by a HIPAA-covered entity – a healthcare provider, health plan or health insurer, or a aid clearinghouse – or a business associate of a HIPAA-covered entity, in relation to the availability of aid or payment for aid services.

It is not only past and current medical info that’s considered letter under HIPAA Rules, however also future info concerning medical conditions or physical and mental health related to the provision of care or payment for care. phi is health info in any kind, together with physical records, electronic records, or spoken info.

Therefore, letter includes health records, medical histories, lab check results, and medical bills. basically, all health info is considered letter once it includes individual identifiers. Demographic info is additionally thought of phi underneath HIPAA Rules, as square measure several common identifiers like patient names, Social Security numbers, Driver’s license numbers, insurance details, and birth dates, once they square measure connected with health info.

The eighteen identifiers that create health info letter are:

Names

Dates, except year

phonephone numbers

Geographic information

FAX numbers

Social Security numbers

Email addresses

case history numbers

Account numbers

Health arrange beneficiary numbers

Certificate/license numbers

Vehicle identifiers and serial numbers together with license plates

Web URLs

Device identifiers and serial numbers

net protocol addresses

Full face photos and comparable pictures

Biometric identifiers (i.e. retinal scan, fingerprints)

Any distinctive identifying variety or code

One or a lot of of those identifiers turns health info into letter, and phi HIPAA Privacy Rule restrictions can then apply that limit uses and disclosures of the data. HIPAA lined entities and their business associates will ought to guarantee applicable technical, physical, and body safeguards are enforced to make sure the confidentiality, integrity, and availability of phi as stipulated within the HIPAA Security Rule.

A thin Whois model is a type of data model that is used by some domain registrars for storing and looking up Whois information. In a thin Whois model, the registrar only stores the basic information about the domain, such as the domain name, the registrar name, the name servers, and the registration and expiration dates. The rest of the information, such as the contact details of the domain owner, the administrative contact, and the technical contact, is stored by the registry that manages the top-level domain (TLD) of the domain. For example, the registry for .com and .net domains is Verisign, and the registry for .org domains is Public Interest Registry. When a Whois lookup is performed on a domain that uses a thin Whois model, the registrar’s Whois server only returns the basic information and refers the query to the registry’s Whois server for the complete information1.

As a hacker, if you are unable to gather complete Whois information from the registrar for a particular set of data, it might be because the domain’s registrar is using a thin Whois model and the registry’s Whois server is not responding or providing the information. This could be due to various reasons, such as network issues, server errors, rate limits, privacy policies, or legal restrictions. Therefore, the probable data model being utilized by the domain’s registrar for storing and looking up Whois information is a thin Whois model working correctly.

The given command is used to establish a null session connection with the IPC$ share on a Windows machine. IPC$ (Inter-Process Communication) is a special hidden share used for Windows inter-process communication, and when connected with blank credentials, it allows anonymous access to certain system information — a common step in enumeration.

Command breakdown:

net use \target\ipc$ "" /u:""

? Initiates a connection using a blank username and password (null session).

From CEH v13 Courseware:

Module 04: Enumeration

Topic: Null Sessions and SMB Enumeration

CEH v13 Study Guide states:

“A null session allows unauthorized users to connect to a Windows machine and extract information like usernames, shares, and policies. Null sessions exploit the default settings of the IPC$ share and are typically initiated using net use commands.”

Incorrect Options:

A/B: Accessing the etc/passwd or SAM directly is not the function of this command.

C: Samba uses SMB, but this is targeting a Windows system.

E: Cisco router enumeration involves SNMP, not Windows IPC$.

A Stealth or Tunneling Virus is designed specifically to evade detection by antivirus software and system monitoring tools. These viruses work by intercepting and modifying the operating system’s service call interrupts (such as INT 13h and INT 21h in DOS systems), which are used to access files or system services.

By hooking into these interrupts, the virus can return clean or forged data to antivirus scanners, thus hiding its malicious presence from detection tools.

Tunneling viruses may also operate at a lower level to evade even more advanced antivirus detection methods, making them particularly dangerous and hard to detect.

Reference – CEH v13 Official Study Guide:

Module 6: Malware Threats

Section: Types of Viruses

Quote:

“Tunneling viruses attempt to avoid detection by antivirus programs by installing themselves in the interrupt handler chain. These viruses intercept operating system calls to conceal their activities.”

Incorrect Options Explained:

A. Macro viruses target applications like Microsoft Word/Excel and use embedded macros, but do not alter service call interrupts.

C. Cavity viruses insert code into empty spaces in files without changing the file size but do not modify interrupts.

D. Polymorphic viruses mutate their code to avoid signature-based detection but do not typically interfere with system interrupts directly.

CEH v13 explains that multi-vector DDoS attacks, especially those combining volumetric reflection (DNS amplification) with application-layer exhaustion (Slowloris), require multi-layered mitigation. Standard firewalls and IPS devices cannot handle large-scale distributed attacks without causing collateral damage to legitimate traffic. CEH emphasizes the need for hybrid DDoS protection, combining on-premises appliances for real-time local filtering with cloud-based scrubbing centers capable of absorbing massive volumetric floods. Cloud scrubbing removes malicious traffic upstream, while on-prem devices mitigate application-layer anomalies. Increasing bandwidth (Option A) is ineffective against reflection attacks. IPS (Option B) cannot handle Slowloris-style partial requests at scale. Blocking all external DNS/HTTP (Option C) would deny service to legitimate users. The correct CEH-aligned solution is hybrid DDoS mitigation services.

Comprehensive and Detailed Explanation:

Tshark is the command-line version of Wireshark. The correct syntax for filtering packets from a subnet:

sudo tshark -f "net 192.168.8.0/24"

This captures only the traffic from that IP range. It’s ideal for cron jobs and automated monitoring.

From CEH v13 Courseware:

Module 8: Sniffing ? Tshark and Wireshark Usage

Server-side request forgery (also called SSRF) is a net security vulnerability that allows an assaulter to induce the server-side application to make http requests to associate arbitrary domain of the attacker’s choosing.

In typical SSRF examples, the attacker might cause the server to make a connection back to itself, or to other web-based services among the organization’s infrastructure, or to external third-party systems.

Another type of trust relationship that often arises with server-side request forgery is where the application server is able to interact with different back-end systems that aren’t directly reachable by users. These systems typically have non-routable private informatics addresses. Since the back-end systems normally ordinarily protected by the topology, they typically have a weaker security posture. In several cases, internal back-end systems contain sensitive functionality that may be accessed while not authentication by anyone who is able to act with the systems.

In the preceding example, suppose there’s an body interface at the back-end url https://192.168.0.68/admin. Here, an attacker will exploit the SSRF vulnerability to access the executive interface by submitting the following request:

POST /product/stock HTTP/1.0

Content-Type: application/x-www-form-urlencoded

Content-Length: 118

stockApi=http://192.168.0.68/admin

Objectives of Footprinting Draw Network Map - Combining footprinting techniques with tools such as Tracert allows the attacker to create diagrammatic representations of the target organization’s network presence. Specficially, it allows attackers to draw a map or outline of the target organization’s network infrastructure to know about the actual environment that they are going to break into. These network diagrams can guide the attacker in performing an attack. (P.114/98)

DNS cache snooping is an enumeration technique where the attacker queries a DNS server to check whether a specific domain has been recently resolved by the server (i.e., it exists in the cache). If a positive response is received with low latency, it indicates that the domain was visited recently.

Key points:

Used to infer user browsing habits or visited domains.

Helps attackers identify user interests or potential targets.

Incorrect Options:

A. DNS zone walking is used to list all domain names in a DNS zone (with misconfigured DNS servers), not for cached record inspection.

C. DNSSEC zone walking applies only when DNSSEC is misconfigured.

D. DNS cache poisoning is a manipulation technique, not a passive enumeration method.

Reference – CEH v13 Official Courseware:

Module 04: Enumeration

Section: “DNS Enumeration”

Subsection: “DNS Cache Snooping and Timing Analysis”

Tool Reference: dig, nslookup

===========

A digital signature mechanism is a cryptographic concept that you should propose to the team to verify the integrity of the data upon retrieval. A digital signature mechanism works as follows:

A digital signature is a mathematical scheme that allows the sender of a message to sign the message with their private key, and allows the receiver of the message to verify the signature with the sender’s public key. A digital signature provides two security services: authentication and non-repudiation. Authentication means that the receiver can confirm the identity of the sender, and non-repudiation means that the sender cannot deny sending the message12.

A digital signature mechanism consists of three algorithms: key generation, signing, and verification. Key generation produces a pair of keys: a private key for the sender and a public key for the receiver. Signing takes the message and the private key as inputs, and outputs a signature. Verification takes the message, the signature, and the public key as inputs, and outputs a boolean value indicating whether the signature is valid or not12.

A digital signature mechanism can be implemented using various cryptographic techniques, such as hash-based signatures, RSA signatures, or elliptic curve signatures. A common method is to use a hash function to compress the message into a fixed-length digest, and then use an asymmetric encryption algorithm to encrypt the digest with the private key. The encrypted digest is the signature, which can be decrypted with the public key and compared with the hash of the message to verify the integrity12.

A digital signature mechanism can ensure the integrity of the data upon retrieval, because:

A digital signature is unique to the message and the sender, and it cannot be forged or altered by anyone else. If the message or the signature is modified in any way, the verification will fail and the receiver will know that the data is corrupted or tampered with12.

A digital signature is independent of the encryption or hashing of the data, and it can be applied to any type of data, regardless of its format or size. The encryption or hashing of the data can provide confidentiality and efficiency, but they cannot provide integrity or authentication by themselves. A digital signature can complement the encryption or hashing of the data by providing an additional layer of security12.

The other options are not as suitable as option B for the following reasons:

A. Implement a block cipher mode of operation: This option is not relevant because it does not address the integrity verification issue, but the encryption issue. A block cipher mode of operation is a method of applying a block cipher, which is a symmetric encryption algorithm that operates on fixed-length blocks of data, to a variable-length message. A block cipher mode of operation can provide different security properties, such as confidentiality, integrity, or authenticity, depending on the mode. However, a block cipher mode of operation cannot provide a digital signature, which is a form of asymmetric encryption that uses a pair of keys3 .

C. Suggest using salt with hashing: This option is not sufficient because it does not provide a digital signature, but only a hash value. Salt is a random value that is added to the input of a hash function, which is a one-way function that maps any data to a fixed-length digest. Salt can enhance the security of hashing by making it harder to perform brute-force attacks or dictionary attacks, which are methods of finding the input that produces a given hash value. However, salt cannot provide a digital signature, which is a two-way function that uses a pair of keys to sign and verify a message .

D. Switch to elliptic curve cryptography: This option is not specific because it does not specify a digital signature mechanism, but only a type of cryptography. Elliptic curve cryptography is a branch of cryptography that uses mathematical curves to generate keys and perform operations. Elliptic curve cryptography can be used to implement various cryptographic techniques, such as encryption, hashing, or digital signatures. However, elliptic curve cryptography is not a digital signature mechanism by itself, but rather a tool that can be used to create one .

In CEH v13 Module 02: Footprinting and Reconnaissance, and Module 03: Scanning Networks, several tools and techniques are introduced for analyzing public IP addresses when investigating a security alert.

Let’s evaluate the options:

A. DNS: Domain Name System (DNS) is essential in mapping IPs to domains. Reverse DNS lookups can reveal if the IP is associated with a malicious domain, and forward lookups can confirm legitimacy.

B. Whois: WHOIS records are crucial for identifying IP ownership, registration data, and abuse contacts. It helps assess if the IP belongs to a known threat actor or suspicious hosting provider.

C. Geolocation: Helps you understand where the IP is physically located. If the IP is in a country known for cybercrime or doesn’t match your user's location, it raises red flags.

D. ARP (Address Resolution Protocol): ? ARP is local to Layer 2 and works only within a LAN (Local Area Network). ARP cannot resolve or analyze public IP addresses which operate in Layer 3 of the OSI model.

Thus, ARP is the least relevant when analyzing a public IP address, as it deals with MAC-to-IP mapping only in local environments.

Comprehensive and Detailed Explanation:

Wireshark on Windows requires WinPcap to operate. WinPcap is a packet capture library that allows network interfaces to operate in promiscuous mode, which is essential for sniffing traffic.

From CEH v13 Courseware:

Module 8: Sniffing ? Sniffing Tools ? WinPcap for Windows

Passive Assessment Passive assessments sniff the traffic present on the network to identify the active systems, network services, applications, and vulnerabilities. Passive assessments also provide a list of the users who are currently accessing the network.

Email spoofing is the fabrication of an email header in the hopes of duping the recipient into thinking the email originated from someone or somewhere other than the intended source. Because core email protocols do not have a built-in method of authentication, it is common for spam and phishing emails to use said spoofing to trick the recipient into trusting the origin of the message.

The ultimate goal of email spoofing is to get recipients to open, and possibly even respond to, a solicitation. Although the spoofed messages are usually just a nuisance requiring little action besides removal, the more malicious varieties can cause significant problems and sometimes pose a real security threat.

==================================================================

A cloud carrier acts as an intermediary that provides connectivity and transport of cloud services between cloud consumers and cloud providers.

Cloud carriers provide access to consumers through network, telecommunication and other access devices. for instance, cloud consumers will obtain cloud services through network access devices, like computers, laptops, mobile phones, mobile web devices (MIDs), etc.

The distribution of cloud services is often provided by network and telecommunication carriers or a transport agent, wherever a transport agent refers to a business organization that provides physical transport of storage media like high-capacity hard drives.

Note that a cloud provider can started SLAs with a cloud carrier to provide services consistent with the level of SLAs offered to cloud consumers, and will require the cloud carrier to provide dedicated and secure connections between cloud consumers and cloud providers.

A Ping of Death attack is a type of DoS attack that exploits a vulnerability in the IP protocol that allows packets to be fragmented and reassembled at the destination. The attacker sends a malformed packet that exceeds the maximum size of 65,535 bytes, which causes the target system to crash or become unstable when it tries to reassemble the packet. This attack can affect various operating systems and devices, such as routers, switches, and firewalls. A Ping of Death attack can be detected by monitoring the network traffic for unusually large packets or ICMP messages. References:

Ping of Death (PoD) Attack

Denial-of-Service Attacks: History, Techniques & Prevention

What is a denial-of-service (DoS) attack?

Pharming is a cyberattack technique in which malicious code is used to redirect a website’s traffic to a fraudulent or malicious website without the user's knowledge. This redirection typically occurs through:

DNS poisoning or host file modification

Exploitation of vulnerabilities in DNS servers or user machines

Pharming aims to collect sensitive data (like usernames, passwords, credit card details) by making users believe they are interacting with a legitimate website when, in fact, they are on a fake one.

As per CEH v13 Official Courseware:

Pharming is a server-side or client-side attack that manipulates how URLs are resolved.

It differs from phishing in that it does not rely on fake emails or social engineering but rather on redirecting web traffic via compromised DNS infrastructure or local configuration.

Incorrect Options:

A. Spimming is the use of spam over instant messaging.

C. Phishing involves tricking users through fake emails or messages.

D. Spear-phishing is a targeted version of phishing directed at specific individuals or roles.

Reference – CEH v13 Official Courseware:

Module 09: Social Engineering

Section: “Phishing and Pharming Attacks”

Subsection: “Differences Between Phishing and Pharming”

A Slow HTTP POST attack is a type of denial-of-service (DoS) attack that exploits the way web servers handle HTTP requests. The attacker sends a legitimate HTTP POST header to the web server, specifying a large amount of data to be sent in the request body. However, the attacker then sends the data very slowly, keeping the connection open and occupying the server’s resources. The attacker can launch multiple such connections, exceeding the server’s capacity to handle concurrent requests and preventing legitimate users from accessing the web server.

The attack duration D is given by the formula D = a * b, where a is the number of connections and b is the hold-up time per connection. The attacker intends to maximize D by manipulating a and b. The server can manage m connections per second, but any connections exceeding m will overwhelm the system. Therefore, the scenario that is most likely to result in the longest duration of server unavailability is the one where a > m and b is the largest. Among the four options, this is the case for option B, where a = 100, m = 90, and b = 15. In this scenario, D = 100 * 15 = 1500 seconds, which is the longest among the four options. Option A has a larger b, but a < m, so the server can handle the connections without being overwhelmed. Option C has a > m, but a smaller b, so the attack duration is shorter. Option D has a > m, but a smaller b and a smaller difference between a and m, so the attack duration is also shorter. 

CHNTPW (Change NT Password) is a Linux-based utility that allows attackers or administrators to:

Reset Windows user account passwords

Unlock disabled or locked user accounts

Remove password protection without knowing the original password

It works by editing the Windows SAM (Security Account Manager) file located in the Windows system directory.

Reference – CEH v13 Official Study Guide:

Module 5: System Hacking

Quote:

“CHNTPW is a tool that can reset or change passwords on Windows systems by directly editing the SAM database. It is commonly run from a Linux LiveCD.”

Incorrect Options:

A. John the Ripper is for cracking passwords, not resetting them directly.

B. SET (Social Engineering Toolkit) is for phishing and payloads, not password resets.

D. Cain & Abel is a password recovery tool for Windows but runs on Windows, not Linux.

===========

Information Gathering from Robots.txt File A website owner creates a robots.txt file to list the files or directories a web crawler should index for providing search results. Poorly written robots.txt files can cause the complete indexing of website files and directories. If confidential files and directories are indexed, an attacker may easily obtain information such as passwords, email addresses, hidden links, and membership areas. If the owner of the target website writes the robots.txt file without allowing the indexing of restricted pages for providing search results, an attacker can still view the robots.txt file of the site to discover restricted files and then view them to gather information. An attacker types URL/robots.txt in the address bar of a browser to view the target website’s robots.txt file. An attacker can also download the robots.txt file of a target website using the Wget tool. Certified Ethical Hacker(CEH) Version 11 pg 1650

The SOA (Start of Authority) record contains key DNS parameters, including TTL (Time To Live). The components of an SOA record are in this order:

(domain) IN SOA (Primary Name Server) (Responsible party) (Serial) (Refresh) (Retry) (Expire) (Minimum TTL)

Given:

Rutgers.edu. SOA NS1.Rutgers.edu ipad.college.edu (200302028 3600 3600 604800 2400.)

Field breakdown:

Serial: 200302028

Refresh: 3600 seconds

Retry: 3600 seconds

Expire: 604800 seconds

Minimum TTL: 2400 seconds ? This is the TTL value

From CEH v13 Courseware:

Module 3: Scanning Networks

Topic: DNS Enumeration and Zone Transfers

Subsection: Understanding DNS Records

CEH v13 Study Guide states:

“In an SOA record, the last value is the Minimum TTL — the amount of time other DNS servers should cache resource records for the zone.”

Incorrect Options:

A: Serial number

B: Refresh interval

C: Expiry interval

E/F: Arbitrary, not part of the SOA shown

The nbtstat command is a Windows utility that displays NetBIOS over TCP/IP (NetBT) protocol statistics, NetBIOS name tables, and the NetBIOS name cache. However, the nbtstat command does not support IPv6 addresses, which are the standard format for the Internet Protocol version 6 (IPv6). Therefore, using the nbtstat command with IPv6 addresses will result in an error message or no output. To enumerate NetBIOS names on a network that uses IPv6, you should switch to an enumeration tool that supports IPv6, such as Nmap, which is a network scanning and security auditing tool. Nmap has a scripting engine (NSE) that allows users to write and execute scripts for various network tasks, including NetBIOS enumeration. Nmap can also detect the operating system, services, and vulnerabilities of the target machines, regardless of the IP version they use. References:

Nbtstat Command - Computer Hope

Nbtstat CMD: Windows Network Command Line Prompt

[Nmap Scripting Engine (NSE) Documentation]

LAN Manager (LM) hashes are legacy password hashing methods used in older Windows systems (including Windows 2000 for backward compatibility). LM hashing works by:

Converting the password to uppercase.

Padding or truncating it to 14 characters.

Splitting it into two 7-character halves.

Using each half as a DES key to encrypt a known constant ("KGS!@#$%").

Therefore, LM hashing uses the DES (Data Encryption Standard) algorithm.

From CEH v13 Official Courseware:

Module 6: Malware Threats ? Password Storage and LM Hash Structure

The PSH (Push) flag in TCP instructs the sending system to:

Immediately deliver data to the application.

Avoid waiting for additional buffered data to form a full segment.

This is important in interactive communications like Telnet or SSH, where the delay in transmission would degrade the user experience.

From CEH v13 Courseware:

Module 3: Scanning Networks ? TCP Flags and Packet Structure

CEH training emphasizes that mobile applications frequently mishandle local storage, leaving sensitive data such as tokens, passwords, API keys, or personal information unencrypted within SQLite databases, shared preferences, or flat-file storage. When encryption is absent or improperly implemented, attackers can directly access this data through filesystem extraction, Android Debug Bridge (ADB) access, physical device access, or rooted environments. CEH identifies “Insecure Data Storage” as one of the most critical mobile vulnerabilities because it bypasses server-side defenses entirely. Since the vulnerability specifically concerns data at rest, the most direct and effective exploitation method is to retrieve the locally stored unencrypted data. SQL injection (Option B) evaluates backend security, not device storage. XSS (Option C) is a web attack and unrelated to local encryption. Brute-forcing credentials (Option D) is unnecessary when sensitive information is already stored insecurely. Therefore, accessing local storage is the correct exploitation method.

The Snort rule in the image is detecting suspicious bind attempts over DCERPC (Distributed Computing Environment/Remote Procedure Call), specifically targeting ports 135 (RPC) and 445 (SMB) with crafted content. The rule references CVE CAN-2003-0352.

CVE-2003-0352 is associated with the DCOM RPC vulnerability in Microsoft Windows that was exploited by the MS Blaster (also known as Lovsan) worm in 2003.

Key Indicators from the Snort Rule:

alert tcp $EXTERNAL_NET any -> $HOME_NET 135

content includes DCERPC binding pattern (|05| and |0b| with specific binary patterns)

Reference to CVE-2003-0352

Class type: attempted-admin

The MS Blaster worm exploited this vulnerability by sending a specially crafted RPC request to port 135, allowing remote code execution.

From CEH v13 Courseware:

Module 6: Malware Threats

Module 11: Session Hijacking

Discussion of historic worms and their exploit signatures, including MS Blaster.

Incorrect Options:

A. WebDav: Typically uses HTTP/HTTPS and was exploited by Nimda.

B. SQL Slammer: Targeted UDP port 1434 (SQL Server), not TCP 135/445.

D. MyDoom: Spread via email and exploited Windows file-sharing mechanisms (port 3127), not DCERPC.

The TCP three-way handshake is the foundational mechanism used to establish a reliable connection between two devices. The sequence is as follows:

The client sends a SYN (synchronize) packet to the server to initiate the connection.

The server replies with a SYN-ACK (synchronize-acknowledge) packet.

The client sends an ACK (acknowledge) packet back to the server.

Therefore, the connection starts with a SYN packet from the client.

A hybrid encryption system is a system that combines the advantages of both asymmetric and symmetric encryption algorithms. Asymmetric encryption, such as RSA, uses a pair of keys: a public key and a private key, which are mathematically related but not identical. Asymmetric encryption can provide key exchange, authentication, and non-repudiation, but it is slower and less efficient than symmetric encryption. Symmetric encryption, such as AES, uses a single key to encrypt and decrypt data. Symmetric encryption is faster and more efficient than asymmetric encryption, but it requires a secure way to share the key.

In a hybrid encryption system, RSA encryption is used for key exchange, and AES encryption is used for data encryption. This way, the system can benefit from the security of RSA and the speed of AES. However, the system also depends on the key sizes of both algorithms, which affect the security and performance of the system.

The key size of RSA encryption determines the number of bits in the public and private keys. The larger the key size, the more secure the encryption, but also the slower the key generation and encryption/decryption processes. The time complexity of generating an RSA key pair is O(n*2), where n is the key size in bits. This means that the time required to generate an RSA key pair increases quadratically with the key size. For example, if it takes 1 second to generate a 1024-bit RSA key pair, it will take 4 seconds to generate a 2048-bit RSA key pair, and 16 seconds to generate a 4096-bit RSA key pair.

The key size of AES encryption determines the number of bits in the symmetric key. The larger the key size, the more secure the encryption, but also the more rounds of encryption/decryption are needed. The time complexity of AES encryption is O(n), where n is the key size in bits. This means that the time required to encrypt/decrypt data increases linearly with the key size. For example, if it takes 1 second to encrypt/decrypt data with a 128-bit AES key, it will take 2 seconds to encrypt/decrypt data with a 256-bit AES key, and 4 seconds to encrypt/decrypt data with a 512-bit AES key.

An attacker has developed a quantum algorithm with time complexity O((log n)*2) to crack RSA encryption. This means that the time required to break RSA encryption decreases exponentially with the key size. For example, if it takes 1 second to break a 1024-bit RSA encryption, it will take 0.25 seconds to break a 2048-bit RSA encryption, and 0.0625 seconds to break a 4096-bit RSA encryption. This makes RSA encryption vulnerable to quantum attacks, unless the key size is very large.

Given n=4000 and variable AES key size, the scenario that is likely to provide the best balance of security and performance is C. AES key size=192 bits. This configuration is a compromise between options A and B, providing moderate security and performance. Option A, AES key size=128 bits, provides less security than option C, but RSA key generation and AES encryption will be faster. Option B, AES key size=256 bits, provides more security than option C, but RSA key generation may be slow. Option D, AES key size=512 bits, provides the highest level of security, but at a significant performance cost due to the large AES key size.

A counter-based authentication system is based on the HOTP (HMAC-Based One-Time Password) algorithm. It uses a shared secret and a moving counter to generate a one-time password (OTP). Each time the counter is incremented, a new OTP is generated and encrypted using the secret key.

Reference – CEH v13 Official Study Guide:

Module 5: System Hacking

Quote:

“HOTP generates a one-time password using a counter value and a secret key. This is a form of two-factor authentication, and the passwords are encrypted.”

Incorrect Options Explained:

A & B. These describe biometric systems, not counter-based OTPs.

D. Virtual passwords from passphrases are not counter-based systems.

===========

ARP (Address Resolution Protocol) spoofing/poisoning is a common attack in which an attacker sends falsified ARP messages to associate their MAC address with the IP address of another host. To defend against ARP spoofing:

A. Port Security: Limits the number of MAC addresses per port; prevents MAC flooding and spoofing.

B. ARPwatch: Monitors ARP traffic and alerts on unusual changes.

D. Static ARP Entries: Prevent ARP responses from overwriting MAC-IP mappings, effective in small networks.

From CEH v13 Official Courseware:

Module 8: Sniffing

Module 11: Session Hijacking

Module 20: Network Security

Incorrect Options:

C: Firewalls operate at Layer 3+; ARP is a Layer 2 protocol, so firewalls don’t prevent ARP spoofing.

E: Static IP addresses do not prevent ARP poisoning.

Adware, or advertising supported computer code, is computer code that displays unwanted advertisements on your pc. Adware programs can tend to serve you pop-up ads, will modification your browser’s homepage, add spyware and simply bombard your device with advertisements. Adware may be a additional summary name for doubtless unwanted programs. It’s roughly a virulent disease and it’s going to not be as clearly malicious as a great deal of different problematic code floating around on the net. create no mistake concerning it, though, that adware has to return off of no matter machine it’s on. Not solely will adware be extremely annoying whenever you utilize your machine, it might additionally cause semipermanent problems for your device.

Adware a network users the browser to gather your internet browsing history so as to ’target’ advertisements that appear tailored to your interests. At their most innocuous, adware infections square measure simply annoying. as an example, adware barrages you with pop-up ads that may create your net expertise markedly slower and additional labor intensive.

Remote File Inclusion occurs when an application allows external resources to be loaded from user-controlled input. CEH teaches that an attacker can supply a remote URL pointing to a malicious script (for example, a PHP shell). When the vulnerable application includes this external file, the attacker's code executes on the server. This can lead to full system compromise, remote command execution, or lateral movement.

Burp Suite is a comprehensive web vulnerability scanner and testing suite widely used in penetration testing and ethical hacking.

Key features include:

Intercepting proxy: Allows inspection and modification of traffic between the browser and target server.

Session hijacking/testing tools

Intruder and Repeater modules for customized payload injection

Sequencer module for testing session token randomness

Extensibility through plugins and custom scripts

Incorrect Options:

A. Nmap is a network scanning tool, not used for intercepting web traffic.

C. CxSAST (Checkmarx) is a static application security testing (SAST) tool.

D. Wireshark is a packet analyzer but does not include intercepting proxy features or token testing.

Reference – CEH v13 Official Courseware:

Module 14: Hacking Web Applications

Section: “Burp Suite as a Web Vulnerability Testing Tool”

CEH iLab: Using Burp Suite for Web App Testing

===========

Comprehensive and Detailed Explanation:

To identify inconsistencies in secure asset records and confirm that systems meet baseline security standards, vulnerability scanning and checking data items (e.g., configuration settings, software versions) is essential. This helps the analyst discover gaps between expected and actual system states.

From CEH v13 Official Curriculum:

Module 5: Vulnerability Assessment ? Security Assessment Techniques

“Automated vulnerability scanners and asset inventories help validate that systems are compliant with security baselines.”

https://en.wikipedia.org/wiki/Evil_twin_(wireless_networks)

An evil twin attack is a hack attack in which a hacker sets up a fake Wi-Fi network that looks like a legitimate access point to steal victims’ sensitive details. Most often, the victims of such attacks are ordinary people like you and me.

The attack can be performed as a man-in-the-middle (MITM) attack. The fake Wi-Fi access point is used to eavesdrop on users and steal their login credentials or other sensitive information. Because the hacker owns the equipment being used, the victim will have no idea that the hacker might be intercepting things like bank transactions.

An evil twin access point can also be used in a phishing scam. In this type of attack, victims will connect to the evil twin and will be lured to a phishing site. It will prompt them to enter their sensitive data, such as their login details. These, of course, will be sent straight to the hacker. Once the hacker gets them, they might simply disconnect the victim and show that the server is temporarily unavailable.

ADDITION: It may not seem obvious what happened. The problem is in the question statement. The attackers were not Alice and John, who were able to connect to the network without a password, but on the contrary, they were attacked and forced to connect to a fake network, and not to the real network belonging to Jane.

Bob wants Alice to verify that the message hasn’t been tampered with. This is a use case for ensuring data integrity and authenticity. The process described matches the creation of a digital signature:

Bob computes a checksum (typically a cryptographic hash) of the message.

Then, he encrypts this checksum (hash) using his own private key.

Alice receives the message and decrypts the checksum using Bob’s public key.

If the decrypted checksum matches the hash she computes from the received message, she confirms the message’s integrity and authenticity.

This is a fundamental principle of digital signatures.

Incorrect Options:

A. Alice's private key is never used by others; it's confidential.

B. Encrypting with Alice’s public key ensures confidentiality, not authenticity.

D. Bob’s public key is used by the receiver to verify authenticity, not for encryption in this context.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Digital Signatures”

Subsection: “Using Private Keys to Sign and Public Keys to Verify”

CEH Engage Lab: Email Signing and Verification

===========

https://us-cert.cisa.gov/ncas/alerts/TA18-201A

Currently, Emotet uses five known spreader modules: NetPass.exe, WebBrowserPassView, Mail PassView, Outlook scraper, and a credential enumerator. Credential enumerator is a self-extracting RAR file containing two components: a bypass component and a service component. The bypass component is used for the enumeration of network resources and either finds writable share drives using Server Message Block (SMB) or tries to brute force user accounts, including the administrator account. Once an available system is found, Emotet writes the service component on the system, which writes Emotet onto the disk. Emotet’s access to SMB can result in the infection of entire domains (servers and clients).

LM hashes are split into two 16-character halves (each representing 7-character blocks). If the original password is less than 8 characters, the second half of the LM hash will always be a constant:

"AAD3B435B51404EE"

This known value is used to pad the second half of the password, and it signals that the original password was 7 characters or fewer.

In the options:

B. 44EFCE164AB921CQAAD3B435B51404EE ? ends with AAD3B435B51404EE ? < 8 chars

E. B757BF5C0D87772FAAD3B435B51404EE ? also ends with AAD3B435B51404EE ? < 8 chars

From CEH v13 Official Courseware:

Module 6: Malware Threats ? LM Hash Weaknesses

CEH teaches that insufficient input validation on mobile applications enables code injection attacks. Injecting JavaScript or crafted payloads into fields validates whether the application improperly processes untrusted data. If executed, it confirms that the app is vulnerable to injection-based attacks.

While perimeter defenses like firewalls and IPS provide a layer of protection, internal systems (such as network elements) must also be hardened. This includes:

Enforcing strong authentication

Applying regular patches and updates

Conducting vulnerability assessments and security audits

Security should be layered (defense in depth), and reliance on perimeter defense alone is insufficient.

Reference – CEH v13 Official Study Guide:

Module 3: Scanning Networks / Module 18: Incident Response

Quote:

“Internal systems must be hardened with secure configurations and tested regularly. A layered security approach is required even in protected environments.”

Incorrect Options:

B & C. Relying only on perimeter or physical security is not sufficient

D. While backup sites are part of DR, they don’t replace proactive protection

===========

In CEH v13 Module 03: Scanning Networks, the behavior of firewalls in response to ACK scans is described in detail, especially regarding stateful vs. stateless firewalls.

An ACK scan (nmap -sA) is primarily used for firewall rule analysis. Here’s how it works:

When you send a TCP ACK segment:

If the port is closed and no firewall is present, the target should respond with a TCP RST packet.

If a stateless (non-stateful) firewall is used, it typically allows or blocks packets based only on rules about IP addresses, ports, and protocol type, without tracking session state.

If a stateful firewall is used, it keeps track of connection states. Therefore:

An unsolicited ACK packet (not part of any established session) will be silently dropped, because it doesn’t correspond to any active connection.

No RST is sent back because the firewall suppresses it, recognizing it as potentially malicious or out of context.

Therefore:

No RST response = packet was silently dropped.

Silent dropping of unsolicited ACK packets = Stateful Firewall Behavior.

Option Analysis:

A. There is no firewall in place

? Incorrect. If there were no firewall, an RST would be sent from the closed port.

B. This event does not tell you anything about the firewall

? Incorrect. The lack of a response is actually meaningful and implies stateful filtering behavior.

C. It is a stateful firewall

Correct. A stateful firewall inspects the packet, sees no valid session, and drops it silently.

D. It is a non-stateful firewall

? Incorrect. A non-stateful firewall would typically not inspect session state, and you'd still expect to see a response (likely an RST).

Reference from CEH v13 Study Guide and Courseware:

Module 03 – Scanning Networks, Section: Nmap Scanning Techniques ? TCP ACK Scan

CEH Engage Labs – Network Scanning Phase: Firewall Rule Detection using ACK Scans

aLTEr attacks are usually performed on LTE devices Attacker installs a virtual (fake) communication tower between two authentic endpoints intending to mislead the victim This virtual tower is used to interrupt the data transmission between the user and real tower attempting to hijack the active session.

https://alter-attack.net/media/breaking_lte_on_layer_two.pdf

The new aLTEr attack can be used against nearly all LTE connected endpoints by intercepting traffic and redirecting it to malicious websites together with a particular approach for Apple iOS devices.

This attack works by taking advantage of a style flaw among the LTE network — the information link layer (aka: layer-2) of the LTE network is encrypted with AES-CTR however it’s not integrity-protected, that is why an offender will modify the payload.

As a result, the offender is acting a classic man-in-the-middle wherever they’re movement as a cell tower to the victim.

This form of testing is known as Fuzzing. Fuzzing (or fuzz testing) is an automated software testing technique that involves providing invalid, unexpected, or random data as inputs to a computer program. The program is then monitored for exceptions such as crashes, failing built-in code assertions, or potential memory leaks.

In the CEH v13 courseware and study guide:

Module 6: Malware Threats

Subsection: Malware Analysis and Reverse Engineering Techniques

CEH v13 Official Study Guide and iLabs Practical

The CEH v13 guide states:

“Fuzzing is used as a software testing technique that involves sending malformed or unexpected inputs to an application in order to detect vulnerabilities such as buffer overflows, crashes, or unexpected behavior. It is particularly useful during vulnerability assessments and exploit development.”

Thus, Fuzzing helps identify vulnerabilities due to improper input validation and is widely used in vulnerability discovery and exploit testing.

Incorrect Options:

A. Randomizing: Not a recognized security testing method.

B. Bounding: Refers to setting limits or constraints; not relevant here.

C. Mutating: Can be part of fuzzing (mutation-based fuzzing), but not the umbrella term.

MAC flooding is a Layer 2 attack in which an attacker sends a large number of fake MAC addresses to a switch, filling up its CAM (Content Addressable Memory) table. Once the table is full:

The switch enters “fail-open” mode and broadcasts traffic to all ports

The attacker can then sniff sensitive traffic

This attack effectively turns a switch into a hub, facilitating data sniffing.

Incorrect Options:

A. Evil twin is a wireless attack using rogue access points.

B. DNS cache flooding corrupts DNS entries, unrelated to Ethernet.

D. DDoS attacks are about overwhelming systems/services, not Layer 2 memory overflows.

Reference – CEH v13 Official Courseware:

Module 11: Sniffing

Section: “Switch Port Stealing and MAC Flooding”

Subsection: “Layer 2 Attacks and CAM Table Poisoning”

===========

SSL/TLS is a protocol that provides encryption and authentication for data in transit between a client and a server. However, SSL/TLS does not provide any protection against data tampering, which is the alteration, deletion, or insertion of data without authorization or proper validation. Data tampering can compromise the integrity and accuracy of the data, and potentially lead to breaches or fraud. To detect and prevent data tampering, you should implement IPsec in addition to SSL/TLS. IPsec is a protocol that provides encryption, authentication, and integrity for data in transit at the network layer. IPsec uses cryptographic mechanisms, such as digital signatures and hash-based message authentication codes (HMACs), to verify the identity of the sender and the receiver, and to ensure that the data has not been modified during transmission. IPsec can also provide replay protection, which prevents an attacker from retransmitting old or duplicate packets. By combining SSL/TLS and IPsec, you can achieve a higher level of security and reliability for your cloud-based application. References:

EC-Council CEHv12 Courseware Module 18: Cryptography, page 18-20

EC-Council CEHv12 Courseware Module 19: Cloud Computing, page 19-29

A comprehensive guide to data tampering

Tamper Detection

The scenario describes a situation where a hacker infects an internet-facing server and leverages it to perform malicious activities such as sending spam emails, participating in distributed denial-of-service (DDoS) attacks, or hosting spam content. This behavior is characteristic of a Botnet Trojan.

According to the CEH v13 Official Courseware and Study Guide:

A Botnet Trojan is a type of malware that transforms infected machines into bots (also called zombies), which can be remotely controlled by an attacker (bot herder or bot master).

These bots become part of a botnet — a network of compromised machines used for coordinated cyberattacks including:

Sending unsolicited spam emails (junk mail)

Participating in DDoS attacks

Hosting or distributing malware and phishing content

The infected machine can receive commands from a command-and-control (C&C) server and act in concert with other infected machines to amplify attacks or spread malware.

Incorrect Options:

B. Banking Trojans are designed specifically to steal financial data such as online banking credentials.

C. Turtle Trojans is not a valid classification in CEH v13 or cybersecurity literature (may be a distractor).

D. Ransomware Trojans encrypt data and demand a ransom for decryption, not typically used for junk mail or botnet activities.

Reference – CEH v13 Official Courseware:

Module 06: Malware Threats

Section: “Types of Trojans”

Subsection: “Botnet Trojans”

CEH v13 eBook or Study Guide — usually found under “Trojan Classifications by Payload”

Practical labs in CEH Engage and iLabs also demonstrate botnet functionality using tools like Zeus and Emotet in real-world botnet infection scenarios.

Docker uses a client-server design. The docker client talks to the docker daemon, that will the work of building, running, and distributing your docker containers. The docker client and daemon will run on the same system, otherwise you will connect a docker consumer to a remote docker daemon. The docker consumer and daemon communicate using a REST API, over OS sockets or a network interface.

The docker daemon (dockerd) listens for docker API requests and manages docker objects like pictures, containers, networks, and volumes. A daemon may communicate with other daemons to manage docker services.

A pharming attacker tries to send a web site’s traffic to a faux website controlled by the offender, typically for the aim of collection sensitive data from victims or putting in malware on their machines. Attacker tend to specialize in making look-alike ecommerce and digital banking websites to reap credentials and payment card data.

Though they share similar goals, pharming uses a special technique from phishing. “Pharming attacker are targeted on manipulating a system, instead of tricking people into reaching to a dangerous web site,” explains David Emm, principal security man of science at Kaspersky. “When either a phishing or pharming attacker is completed by a criminal, they need a similar driving issue to induce victims onto a corrupt location, however the mechanisms during which this is often undertaken are completely different.”

Risk assessment is a key process in security management that identifies, evaluates, and prioritizes risks to organizational operations and assets. It considers various controls and safeguards to mitigate those risks.

Administrative safeguards are part of the components used in risk assessments and include:

Policies

Procedures

Training

Security awareness programs

Incident response planning

From CEH v13:

Module 1: Introduction to Ethical Hacking

Module 20: Cryptography (as it discusses risk management and governance)

Topic: Security Controls and Risk Management Frameworks

CEH v13 Official Courseware states:

“Administrative controls, also known as administrative safeguards, form a critical component of risk assessments. These include documented security policies, user training, security audits, and incident response plans that help an organization manage and reduce risks.”

Incorrect Options:

B. Physical security is a type of safeguard but not typically referred to as a "component" of a risk assessment itself.

C. DMZ (Demilitarized Zone) is a network architecture concept, not a risk assessment component.

D. Logical interface refers to system architecture and network segmentation—not risk assessment methodology.

One may append the comment “–” operator along with the String for the username and whole avoid executing the password segment of the SQL query. Everything when the — operator would be considered as comment and not dead.

To launch such an attack, the value passed for name could be ’OR ‘1’=‘1’ ; —

Statement = “SELECT * FROM ‘CustomerDB’ WHERE ‘name’ = ‘ ”+ userName + “ ‘ AND ‘password’ = ‘ ” + passwd + “ ‘ ; ”

Statement = “SELECT * FROM ‘CustomerDB’ WHERE ‘name’ = ‘ ’ OR ‘1’=‘1‘;– + “ ‘ AND ‘password’ = ‘ ” + passwd + “ ‘ ; ”

All the records from the customer database would be listed.

Yet, another variation of the SQL Injection Attack can be conducted in dbms systems that allow multiple SQL injection statements. Here, we will also create use of the vulnerability in sure dbms whereby a user provided field isn’t strongly used in or isn’t checked for sort constraints.

This could take place once a numeric field is to be employed in a SQL statement; but, the programmer makes no checks to validate that the user supplied input is numeric.

Variation is an evasion technique whereby the attacker can easily evade any comparison statement. The attacker does this by placing characters such as “' or '1'='1'” in any basic injection statement such as “or 1=1” or with other accepted SQL comments.

Evasion Technique: Variation Variation is an evasion technique whereby the attacker can easily evade any comparison statement. The attacker does this by placing characters such as “' or '1'='1'” in any basic injection statement such as “or 1=1” or with other accepted SQL comments. The SQL interprets this as a comparison between two strings or characters instead of two numeric values. As the evaluation of two strings yields a true statement, similarly, the evaluation of two numeric values yields a true statement, thus rendering the evaluation of the complete query unaffected. It is also possible to write many other signatures; thus, there are infinite possibilities of variation as well. The main aim of the attacker is to have a WHERE statement that is always evaluated as “true” so that any mathematical or string comparison can be used, where the SQL can perform the same.

Reconnaissance is the first phase of ethical hacking and also part of the cyber kill chain. It involves gathering publicly available information about a target, such as employee names, company structure, and branding, which is later used in social engineering or phishing attacks.

Reference – CEH v13 Official Study Guide:

Module 2: Footprinting and Reconnaissance

Quote:

“Reconnaissance involves gathering information from public sources such as websites, social networks, and press releases. This is used to craft targeted phishing messages or exploit organizational weaknesses.”

Incorrect Options Explained:

A & B. Not formal terms in ethical hacking.

D. Enumeration involves interacting with systems to extract technical data.

CEH training outlines the standard methodology for attacking WPA2-PSK networks: capture the 4-way handshake and then attempt offline cracking of the pre-shared key. The most reliable way to force handshake generation is to perform a de-authentication attack using tools like Aireplay-ng. This attack momentarily disconnects a wireless client, forcing it to reauthenticate with the access point. During this reauthentication, the AP and client exchange the 4-way handshake packets necessary for offline cracking. CEH emphasizes that WPA2 encryption itself cannot be brute-forced directly; attackers must obtain the handshake and then apply dictionary or brute-force attacks offline. Attempting XSS or router spoofing does not capture the handshake and is unrelated to WPA2 key extraction. The deauth attack is also a classic wireless attack vector described extensively in CEH because it is effective, does not require interaction with the encryption algorithm, and works regardless of the strength of the AP’s passphrase. Once the handshake is captured, tools such as Hashcat are used to attempt key recovery.

https://en.wikipedia.org/wiki/Presentation_layer

In the seven-layer OSI model of computer networking, the presentation layer is layer 6 and serves as the data translator for the network. It is sometimes called the syntax layer. The presentation layer is responsible for the formatting and delivery of information to the application layer for further processing or display.

Encryption is typically done at this level too, although it can be done on the application, session, transport, or network layers, each having its own advantages and disadvantages. Decryption is also handled at the presentation layer. For example, when logging on to bank account sites the presentation layer will decrypt the data as it is received.

Comprehensive and Detailed Explanation:

LDAP (Lightweight Directory Access Protocol) uses a hierarchical data structure similar to a directory tree. SQL databases use a relational structure with tables, rows, and columns.

Because of its hierarchical nature:

LDAP is excellent for parent-child relationships.

It struggles with representing many-to-many or many-to-one relationships efficiently.

From CEH v13 Courseware:

Module 4: Enumeration ? LDAP Basics

An untethered jailbreak is one that allows a telephone to finish a boot cycle when being pwned with none interruption to jailbreak-oriented practicality.

Untethered jailbreaks area unit the foremost sought-after of all, however they’re additionally the foremost difficult to attain due to the powerful exploits and organic process talent they need. associate unbound jailbreak is sent over a physical USB cable association to a laptop or directly on the device itself by approach of associate application-based exploit, like a web site in campaign.

Upon running associate unbound jailbreak, you’ll be able to flip your pwned telephone off and on once more while not running the jailbreak tool once more. all of your jailbreak tweaks and apps would then continue in operation with none user intervention necessary.

It’s been an extended time since IOS has gotten the unbound jailbreak treatment. the foremost recent example was the computer-based Pangu break, that supported most handsets that ran IOS nine.1. We’ve additionally witnessed associate unbound jailbreak within the kind of JailbreakMe, that allowed users to pwn their handsets directly from the mobile campaign applications programme while not a laptop.

In CEH v13 Module 13: Hacking Web Applications, Server-Side Includes (SSI) is defined as a method for dynamically generating web content through directives embedded in HTML files.

stm File Extension:

Associated with Server Side Includes (SSI).

Files like .stm, .shtml, and .shtm can embed server-side directives.

Vulnerable if user input is improperly handled, allowing command injection or arbitrary file access.

Option Clarification:

A. .stm: Correct – indicates SSI is enabled.

B. .html: Static file, not associated with SSI.

C. .rss: XML feed; irrelevant to SSI.

D. .cms: Generic; doesn’t indicate SSI functionality.

https://www.eccouncil.org/what-is-social-engineering/

This Social Engineering scam involves an exchange of information that can benefit both the victim and the trickster. Scammers would make the prey believe that a fair exchange will be present between both sides, but in reality, only the fraudster stands to benefit, leaving the victim hanging on to nothing. An example of a Quid Pro Quo is a scammer pretending to be an IT support technician. The con artist asks for the login credentials of the company’s computer saying that the company is going to receive technical support in return. Once the victim has provided the credentials, the scammer now has control over the company’s computer and may possibly load malware or steal personal information that can be a motive to commit identity theft.

"A quid pro quo attack (aka something for something” attack) is a variant of baiting. Instead of baiting a target with the promise of a good, a quid pro quo attack promises a service or a benefit based on the execution of a specific action." https://resources.infosecinstitute.com/topic/common-social-engineering-attacks/#:~:text=A%20quid%20pro%20quo%20attack,execution%20of%20a%20specific%20action.

A null user is a special connection made to a Windows system without providing a username or password. In older versions of Windows (NT, 2000, XP), null sessions could be used to anonymously connect to IPC$ share and enumerate:

Users

Groups

Shares

Policies

From CEH v13 Courseware:

Module 4: Enumeration ? Null Sessions

CEH v13 Study Guide states:

“Null users are unauthenticated sessions used to access certain system resources without credentials. These are commonly used in enumeration attacks.”

This falls under Requirement 8 of PCI DSS: "Identify and authenticate access to system components," which supports the objective of implementing strong access control measures.

CEH v13 Reference:

Module 20: Hacking Mobile Platforms and IoT – Compliance Standards

"PCI DSS requires unique identification for each person with access to ensure accountability and access control."

In CEH v13 Module 10: Injection Attacks, the SQL Injection technique is covered extensively. A common attack method is to manipulate the input fields so that the resulting SQL query becomes logically always true, effectively bypassing authentication.

Given the input:

Username: attack' or 1=1 --

Password: 123456

And assuming the original SQL query is:

SELECT * FROM Users WHERE UserName = '' AND UserPassword = '';

When inputs are substituted, the query becomes:

SELECT * FROM Users WHERE UserName = 'attack' or 1=1 --' AND UserPassword = '123456';

The -- sequence is used in SQL to indicate a comment. Everything after -- is ignored by the SQL engine. So the query essentially becomes:CopyEdit

SELECT * FROM Users WHERE UserName = 'attack' or 1=1;

This query is always true due to 1=1, and if the application is vulnerable, it grants access regardless of the password.

Option Analysis:

A. Incorrect – Contains '' (double quote) after attack, which would cause a syntax error due to extra quotation marks.

B. Correct – This is the accurate representation of what the SQL query would look like with a successful injection.

C. Incorrect – The input string is malformed, combining input into one literal string.

D. Incorrect – Misplacement of ' after the comment token -- invalidates the SQL syntax.

Reference from CEH v13 Study Materials:

Module 10 – Injection Attacks, Section: SQL Injection – Authentication Bypass

CEH v13 eCourseware Practical Lab: Exploiting SQL Injection Vulnerability in Login Forms

CEH Engage – Web Application Testing Phase: SQLi Exploitation in Login Panels

When using exploits, you might gain access as only a local user. This limits what you can do on the target machine. You can use Meterpreters 'getsystem` command (https://github.com/rapid7/metasploit-payloads/blob/master/c/meterpreter/source/extensions/priv/elevate.c#L70) to elevate your permissions from a local administrator to SYSTEM. This works by using three elevation techniques.

Footprinting is the first phase of ethical hacking and information gathering. It involves collecting as much information as possible about a target system or organization from public sources (such as websites, social media, WHOIS databases, job postings, etc.) before launching an attack or vulnerability scan.

???? Reference – CEH v13 Official Study Guide, Module 1: Introduction to Ethical Hacking

“Footprinting is the process of gathering information about a target system to find ways to intrude into the system.”

? Incorrect options:

A. Scanning is the next phase, involving probing the network.

C. Enumeration extracts detailed information from services like SNMP, NetBIOS, etc.

D. System Hacking is the actual exploitation phase.

In order to circumvent network protection tools, cybercriminals may forge a TCP session more efficiently by submitting a bogus SYN packet, a series of ACK packets, and at least one RST (reset) or FIN (connection termination) packet. This tactic allows crooks to get around defenses that only keep tabs on incoming traffic rather than analyzing return traffic.

OS fingerprinting helps attackers identify the operating system and version running on a target host. This allows them to:

Determine potential vulnerabilities

Choose appropriate exploits for the OS version and configuration

Bypass ineffective defenses

From CEH v13 Courseware:

Module 3: Scanning Networks

Topic: Active and Passive OS Fingerprinting

CEH v13 Study Guide states:

“Fingerprinting identifies the OS type/version and helps attackers choose specific exploits that apply to that system.”

Incorrect Options:

A: Software enumeration is different from OS fingerprinting.

B/C: Misleading or incorrect in this context.

Zero Trust Networks The Zero Trust model is a security implementation that by default assumes every user trying to access the network is not a trusted entity and verifies every incoming connection before allowing access to the network.It strictly follows the principle, “Trust no one and validate before providing a cloud service or granting access permission.”It also allows companies to impose conditions, such as allowing employees to only access the appropriate resources required for their work role. (P.2997/2981)

Zero Trust is a strategic initiative that helps prevent successful data breaches by eliminating the concept of trust from an organization’s network architecture. Rooted in the principle of “never trust, always verify,” Zero Trust is designed to protect modern digital environments by leveraging network segmentation, preventing lateral movement, providing Layer 7 threat prevention, and simplifying granular user-access control.

Passive reconnaissance is emphasized throughout CEH as an essential method for gathering intelligence without alerting monitoring systems. When the tester cannot interact with the live site, they must rely entirely on third-party archives or cached content stored by search engines or internet archival services. Google’s cache function provides previously stored versions of web pages exactly for this purpose. CEH explains that attackers frequently use cached content to retrieve outdated login portals, administrative pages, exposed directories, or other sensitive elements that may no longer appear on the live web server. Unlike operators such as intext or intitle, which query live indexed metadata, the cache operator retrieves historical snapshots without accessing the target website. The link operator identifies backlinks but does not provide historical page content. Only the cache operator directly supports viewing previous versions of pages passively, aligning perfectly with the requirement to avoid detection while gathering intelligence on legacy web content.

Tess King is attempting to gather all DNS records from a target zone. This process is referred to as a zone transfer (AXFR), which is typically performed by secondary name servers to synchronize DNS data with the primary. If improperly secured, attackers can initiate unauthorized zone transfers to enumerate valuable information such as:

Hostnames

IP addresses

Mail servers

Name servers

CEH v13 defines a zone transfer as a crucial step in DNS enumeration.

From CEH v13 Official Courseware:

Module 3: Scanning Networks

Topic: DNS Enumeration ? Zone Transfers

CEH v13 Study Guide states:

“A zone transfer (AXFR) is a DNS transaction used to replicate DNS databases. Attackers can exploit this feature to extract all DNS information from an improperly secured server.”

Incorrect Options:

A. Zone harvesting is not a formal term.

C. Zone update refers to DNS dynamic update operations (e.g., DDNS).

D. Zone estimate is not a DNS-related process.

User-directed spidering is a technique that allows the hacker to manually browse the target website and use a proxy or spider tool to capture and analyze the traffic. This way, the hacker can discover hidden or dynamic content that standard web spiders may miss due to a specific file in the root directory, such as robots.txt, that instructs them not to crawl certain pages or directories. User-directed spidering can also help the hacker to bypass authentication or authorization mechanisms, as well as identify vulnerabilities or sensitive information in the target website. User-directed spidering can be performed with tools like Burp Suite and WebScarab, which are web application security testing tools that can intercept, modify, and replay HTTP requests and responses, as well as perform various attacks and scans on the target website.

The other options are not likely to achieve the same results as user-directed spidering. Using Photon to retrieve archived URLs of the target website from archive.org may provide some historical information about the website, but it may not reflect the current state or content of the website. Using the Netcraft tool to gather website information may provide some general information about the website, such as its IP address, domain name, server software, or hosting provider, but it may not reveal the specific files or web pages on the website. Examining HTML source code and cookies may provide some clues about the website’s structure, functionality, or user preferences, but it may not expose the hidden or dynamic content that user-directed spidering can discover. References:

User Directed Spidering with Burp

Web Spidering - What Are Web Crawlers & How to Control Them

Web Security: Recon

Mapping the Application for Penetrating Web Applications — 1

SQL injection testing commonly involves using tautology-based payloads such as 1 OR 1=1, which force SQL queries to evaluate as true. CEH explains that this confirms improper input sanitization and exposes whether user-supplied fields directly influence database queries. The result often returns all records, indicating successful injection.

ARP Spoofing Attack ARP packets can be forged to send data to the attacker’s machine.Attackers flood a target computer’s ARP cache with forged entries, which is also known as poisoning. (P.1143/1127)

The most probable subsequent action from the attacker based on the Cyber Kill Chain Methodology is to exploit the malicious payload delivered to the target organization and establish a foothold. This option works as follows:

The Cyber Kill Chain Methodology is a framework that describes the stages of a cyberattack from the perspective of the attacker. It helps defenders to understand the attacker’s objectives, tactics, and techniques, and to design effective countermeasures. The Cyber Kill Chain Methodology consists of seven stages: reconnaissance, weaponization, delivery, exploitation, installation, command and control, and actions on objectives12.

The delivery stage is the third stage in the Cyber Kill Chain Methodology, and it involves sending or transmitting the weaponized payload to the target system. The delivery stage can use various methods, such as email attachments, web links, removable media, or network protocols. The delivery stage aims to reach the target system and bypass any security controls, such as firewalls, antivirus, or email filters12.

The exploitation stage is the fourth stage in the Cyber Kill Chain Methodology, and it involves executing the malicious payload on the target system. The exploitation stage can use various techniques, such as buffer overflows, code injection, or privilege escalation. The exploitation stage aims to exploit a vulnerability or a weakness in the target system and gain access to its resources, such as files, processes, or memory12.

The installation stage is the fifth stage in the Cyber Kill Chain Methodology, and it involves installing a backdoor or a malware on the target system. The installation stage can use various tools, such as rootkits, trojans, or ransomware. The installation stage aims to establish a foothold on the target system and maintain persistence, which means to survive reboots, updates, or scans12.

Therefore, the most probable subsequent action from the attacker based on the Cyber Kill Chain Methodology is to exploit the malicious payload delivered to the target organization and establish a foothold, because:

This action follows the logical sequence of the Cyber Kill Chain Methodology, as it is the next stage after the delivery stage.

This action is consistent with the attacker’s goal, as it allows the attacker to gain access and control over the target system and prepare for further actions.

This action is feasible, as the attacker has already delivered the malicious payload to the target system and may have bypassed some security controls.

The other options are not as probable as option B for the following reasons:

A. The attacker will attempt to escalate privileges to gain complete control of the compromised system: This option is possible, but not the most probable, because it is not the next stage in the Cyber Kill Chain Methodology, but rather a technique that can be used in the exploitation stage or the installation stage. Privilege escalation is a method of increasing the level of access or permissions on a system, such as from a normal user to an administrator. Privilege escalation can help the attacker to gain complete control of the compromised system, but it is not a mandatory step, as the attacker may already have sufficient privileges or may use other techniques to achieve the same goal12.

C. The attacker will initiate an active connection to the target system to gather more data: This option is possible, but not the most probable, because it is not the next stage in the Cyber Kill Chain Methodology, but rather a technique that can be used in the command and control stage or the actions on objectives stage. An active connection is a communication channel that allows the attacker to send commands or receive data from the target system, such as a remote shell or a botnet. An active connection can help the attacker to gather more data from the target system, but it is not a necessary step, as the attacker may already have enough data or may use other techniques to obtain more data12.

D. The attacker will start reconnaissance to gather as much information as possible about the target: This option is not probable, because it is not the next stage in the Cyber Kill Chain Methodology, but rather the first stage. Reconnaissance is the process of collecting information about the target, such as its IP address, domain name, network structure, services, vulnerabilities, or employees. Reconnaissance is usually done before the delivery stage, as it helps the attacker to identify the target and plan the attack. Reconnaissance can be done again after the delivery stage, but it is not the most likely action, as the attacker may already have enough information or may focus on other actions12.

CEH v13 emphasizes that IoT devices must implement secure firmware update mechanisms that enforce authenticity, integrity, and version control. A critical lapse occurs when devices allow rollback to older firmware versions or accept updates without cryptographic validation. This opens the door to “firmware downgrade attacks,” where attackers intentionally install outdated but vulnerable firmware to reintroduce exploitable weaknesses. CEH identifies this as part of insecure update design, one of the most dangerous IoT vulnerabilities because firmware governs device behavior, network communication, and trust boundaries. Without signature verification, integrity checking, and anti-rollback enforcement, attackers can load malicious or deprecated firmware to escalate privileges or pivot deeper into a network. Options B and C represent different categories of IoT weaknesses, and D refers to supply-chain issues, none of which match the described rollback exploitation. Therefore, the vulnerability demonstrated is the absence of secure update mechanisms.

https://en.wikipedia.org/wiki/Nikto_(vulnerability_scanner)

Nikto is a free software command-line vulnerability scanner that scans web servers for dangerous files/CGIs, outdated server software, and other problems. It performs generic and server types specific checks. It also captures and prints any cookies received. The Nikto code itself is free software, but the data files it uses to drive the program are not.

The action that would best protect your web server from potential misconfiguration-based attacks is performing regular server configuration audits. A server configuration audit is a process of reviewing and verifying the security settings and parameters of the server, such as user accounts, permissions, services, ports, protocols, files, directories, logs, and patches. A server configuration audit can help you to identify and fix any security misconfigurations that may expose your server to attacks, such as using default credentials, enabling unnecessary services, leaving open ports, or missing security updates. A server configuration audit can also help you to comply with the security standards and best practices for your server, such as the CIS Benchmarks or the OWASP Secure Configuration Guide12.

The other options are not as effective as option A for the following reasons:

B. Enabling multi-factor authentication for users: This option is not relevant because it does not address the server misconfiguration issue, but the user authentication issue. Multi-factor authentication is a method of verifying the identity of the users by requiring them to provide two or more pieces of evidence, such as a password, a code, or a biometric factor. Multi-factor authentication can enhance the security of the user accounts and prevent unauthorized access, but it does not prevent the server from being attacked due to misconfigured settings or parameters3.

C. Implementing a firewall to filter traffic: This option is not sufficient because it does not prevent the server from being misconfigured, but only limits the exposure of the server to the network. A firewall is a device or software that monitors and controls the incoming and outgoing network traffic based on predefined rules. A firewall can protect the server from external attacks by blocking or allowing certain ports, protocols, or IP addresses. However, a firewall cannot protect the server from internal attacks or from attacks that exploit the allowed traffic. Moreover, a firewall itself can be misconfigured and cause security issues4.

D. Regularly backing up server data: This option is not preventive but reactive, as it does not protect the server from being attacked, but only helps to recover the data in case of an attack. Backing up server data is a process of creating and storing copies of the data on the server, such as files, databases, or configurations. Backing up server data can help you to restore the data in case of data loss, corruption, or deletion due to an attack. However, backing up server data does not prevent the server from being attacked in the first place, and it does not fix the security misconfigurations that may have caused the attack5.

Wired Equivalent Privacy (WEP) may be a security protocol, laid out in the IEEE wireless local area network (Wi-Fi) standard, 802.11b, that’s designed to supply a wireless local area network (WLAN) with A level of security and privacy like what’s usually expected of a wired LAN. A wired local area network (LAN) is usually protected by physical security mechanisms (controlled access to a building, for example) that are effective for a controlled physical environment, but could also be ineffective for WLANs because radio waves aren’t necessarily bound by the walls containing the network. WEP seeks to determine similar protection thereto offered by the wired network’s physical security measures by encrypting data transmitted over the WLAN. encoding protects the vulnerable wireless link between clients and access points; once this measure has been taken, other typical LAN security mechanisms like password protection, end-to-end encryption, virtual private networks (VPNs), and authentication are often put in situ to make sure privacy.

A research group from the University of California at Berkeley recently published a report citing “major security flaws” in WEP that left WLANs using the protocol susceptible to attacks (called wireless equivalent privacy attacks). within the course of the group’s examination of the technology, they were ready to intercept and modify transmissions and gain access to restricted networks. The Wireless Ethernet Compatibility Alliance (WECA) claims that WEP – which is included in many networking products – was never intended to be the only security mechanism for a WLAN, and that, in conjunction with traditional security practices, it’s very effective.

TCP Maimon scan

This scan technique is very similar to NULL, FIN, and Xmas scan, but the probe used here is

FIN/ACK. In most cases, to determine if the port is open or closed, the RST packet should be generated as a response to a probe request. However, in many BSD systems, the port is open if the packet gets dropped in response to a probe.

https://nmap.org/book/scan-methods-maimon-scan.html

How Nmap interprets responses to a Maimon scan probe

Probe Response Assigned State

No response received (even after retransmissions) open|filtered

TCP RST packet closed

ICMP unreachable error (type 3, code 1, 2, 3, 9, 10, or 13) filtered

A cryptographic hash function is used to ensure data integrity. It generates a fixed-length output (digest) from any size of input data. If the data is modified in any way, the resulting hash will change. This allows systems to detect data tampering, ensuring that the data remains unaltered from its original form.

Reference – CEH v13 Official Study Guide:

Module 20: Cryptography

Quote:

“Hash functions are used to ensure the integrity of a message or file by producing a unique digest that changes if the data is modified.”

Incorrect Options:

A. Authentication ensures identity, not data integrity.

B. Confidentiality is achieved via encryption, not hashing.

C. Availability pertains to system uptime and accessibility, not hashes.

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