ECCouncil 312-50v13 Online Access

Comprehensive and Detailed Explanation:

SIEM (Security Information and Event Management) systems aggregate logs and alerts from across the network—servers, routers, firewalls, IDS/IPS, and applications—and correlate that data to identify suspicious or malicious activity.

They provide:

Real-time alerting

Long-term log storage

Compliance reporting

Incident response facilitation

From CEH v13 Courseware:

Module 12: Evading IDS, Firewalls, and Honeypots → SIEM Tools

The command nmap -sX initiates what is known as a Xmas Scan. This type of scan is used to analyze how a target system responds to TCP packets with unusual flag combinations, helping the attacker identify live hosts and open ports without completing a full TCP handshake.

In the Xmas scan, three specific TCP flags are set in the packet:

URG (Urgent)

PSH (Push)

FIN (Finish)

This combination makes the packet appear "lit up like a Christmas tree," hence the name Xmas scan. These packets are sent to target ports to observe the system’s behavior, especially when it does not follow standard RFC 793 behavior.

Closed ports will usually respond with a RST (reset).

Open ports may not respond at all, depending on the operating system and configuration.

This method is typically used to evade detection by firewalls and intrusion detection systems that expect normal TCP traffic patterns.

Reference – CEH v13 Official Study Guide:

Module 03: Scanning Networks, Section: “TCP Scan Types”, Subsection: “Xmas Tree Scan”, Page Reference: typically listed under TCP Flag Scanning Techniques.

CEH v13 iLabs and practical guidance in CEH Engage also cover this scan in reconnaissance simulations.

Incorrect Options Explained:

A. SYN scan (-sS) sets only the SYN flag.

C. ACK scan (-sA) sets the ACK flag.

D. SYN and ACK flags are used in TCP handshake, not in Xmas scan.

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:

Steganography allows someone to hide data (like a spreadsheet or document) within another innocuous-looking file (like an image, video, or audio). This disguises the presence of the data entirely, allowing it to bypass standard data loss prevention (DLP) systems and firewalls, which look for file types and suspicious patterns.

From CEH v13 Courseware:

Module 6: Malware Threats → Steganography and Covert Channels