ECCouncil Updated 312-50v13 Exam Questions and Answers by zohan

CEH v13 explains that WPA2-PSK security relies on the strength of the pre-shared key. Once the 4-way handshake is captured, the attacker must attempt offline cracking. CEH emphasizes that the dictionary attack is the most efficient and commonly used cracking method because it tests structured wordlists, human-derived passwords, and hybrid permutations, dramatically reducing time compared to full brute force. Brute forcing (Option B) is computationally heavy and often impractical unless the password is extremely short. XSS (Option A) and SQL injection (Option D) have no relevance to WPA2 authentication, which occurs at the wireless protocol level, not the router’s web interface. The dictionary attack is highlighted in CEH as the principal technique used with tools like aircrack-ng, hashcat, and pyrit, allowing rapid key testing using optimized GPU or CPU cracking. Thus, Option C is the most effective and CEH-aligned method.

According to the Certified Ethical Hacker (CEH) Reconnaissance and Footprinting module, DNS cache snooping is a passive information-gathering technique used to determine whether a specific DNS record exists in a server’s cache. Attackers commonly use the dig +norecurse option to prevent the DNS server from querying other DNS servers, thereby revealing only cached results.

When a DNS server responds with NOERROR but does not return an answer, it indicates that the domain name itself is valid, but the requested record is not present in the DNS cache. CEH documentation explains that this situation usually occurs when no internal client has recently queried that domain, so the DNS server has no cached entry for it.

Option A is incorrect because a cached record would return a valid answer section.

Option B is incorrect because NOERROR explicitly means the DNS query was processed successfully.

Option D is incorrect because an expired or non-existent domain would typically return NXDOMAIN, not NOERROR.

CEH materials highlight that attackers use DNS cache snooping to infer user behavior, internal browsing habits, and potential target systems within an organization—making option C the correct conclusion.

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”

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A Denial of Service (DoS) attack is a type of cyberattack that aims to make a machine or network resource unavailable to its intended users by flooding it with traffic or requests that consume its resources. A TCP SYN flood attack is a type of DoS attack that exploits the TCP handshake process by sending a large number of SYN requests to the target server, without completing the connection. A UDP flood attack is a type of DoS attack that sends a large number of UDP packets to random ports on the target server, forcing it to check for the application listening at that port and reply with an ICMP packet. An ICMP flood attack is a type of DoS attack that sends a large number of ICMP packets, such as ping requests, to the target server, overwhelming its ICMP processing capacity.

The attacker’s strategy involves a unique mixture of TCP SYN, UDP, and ICMP floods, using ‘r’ packets per second. The server can handle ‘h’ packets per second before it starts showing signs of strain. If ‘r’ surpasses ‘h’, it overwhelms the server, causing it to become unresponsive. The attacker selects ‘r’ as a composite number and ‘h’ as a prime number, making the attack detection more challenging. This is because prime numbers are less predictable and more difficult to factorize than composite numbers, which may hinder the analysis of the attack pattern.

Considering ‘r=2010’ and different values for ‘h’, the scenario that would potentially cause the server to falter is the one where ‘h=1987’ (prime). This is because ‘r’ is greater than ‘h’ by 23 packets per second, which means the server cannot handle the incoming traffic and will eventually run out of resources. The other scenarios would not cause the server to falter, as ‘h’ is either greater than or very close to ‘r’, which means the server can either manage or barely cope with the incoming traffic. References:

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

Denial-of-Service (DoS) Attack: Examples and Common Targets - Investopedia

DDoS Attack Types: Glossary of Terms

What is a Denial of Service (DoS) Attack? | Webopedia