312-50v13 Exam Dumps - Certified Ethical Hacker Exam (CEHv13)

A FIN scan is a classic “stealth” TCP scan technique discussed in CEH network scanning methodology. Unlike a TCP Connect scan, which completes the full three-way handshake and is highly visible in logs, a FIN scan sends a TCP packet with only the FIN flag set to a target port. The scan then interprets the target’s response to infer whether the port is open or closed, without establishing a normal TCP session. This matches the scenario’s requirement to “infer port states without completing a full connection” and to keep visibility low.

The logic relies on expected TCP behavior defined for many TCP/IP stacks. For a closed port, the target typically responds with an RST packet, indicating there is no service listening. For an open port, many systems do not respond at all to an unexpected FIN packet (because it does not correspond to an existing connection). That “no response” behavior becomes the signal the tester uses to suspect the port may be open or filtered. CEH emphasizes that because FIN scans do not perform a handshake, they can be less likely to trigger certain basic connection-based logging, and they generate fewer obvious connection events than TCP Connect scans.

Option D, NULL scan, is also a stealth method, but it uses a packet with no flags set. The question specifically highlights leveraging TCP flags and is commonly mapped in CEH-style questions to FIN scanning as the representative “TCP flag stealth scan.” Option B is too generic, and option A is the most detectable. Therefore, FIN scan best aligns with the described stealth reconnaissance strategy.

Comprehensive Explanation from CEH v13 Courseware:

CEH v13 identifies XML Signature Wrapping (XSW) attacks, also known simply as Wrapping attacks, as a major threat against SOAP-based web services. These attacks exploit weak XML parsing and insufficient validation of signed message components. SOAP messages often include digitally signed sections, but if the server validates the signature without confirming the correct position or structure of the signed elements, attackers can duplicate, move, or wrap signed content inside a modified XML envelope. This allows an attacker to inject malicious payloads while still presenting a valid signature. CEH details how this can lead to unauthorized execution, privilege escalation, or bypassing authentication controls in SOAP APIs. Cloud snooping, cryptanalysis, and IMDS abuse do not involve message duplication or signature misplacement. The scenario precisely matches CEH’s definition of a Wrapping Attack in SOAP/XML security.

The correct answer is C. S/MIME.

S/MIME, or Secure/Multipurpose Internet Mail Extensions, is the email security standard used to provide encryption and digital signing for MIME-based email messages. The CEH cryptography reference describes S/MIME as a standard for public-key encryption and signing of MIME data . It is also defined as a standard for encrypting and authenticating MIME data, primarily used for Internet email .

This directly matches the scenario because the organization requires:

Confidentiality through email encryption.

Authentication through digital signatures.

PKI-based trust using certificates.

Compatibility with Microsoft Outlook environments.

Option A. FlowCrypt is incorrect because it is an email encryption tool/service, mainly associated with OpenPGP-based email encryption, not the standard being asked for.

Option B. RMail is incorrect because it is a secure email service/platform, not the core standardized PKI-based email encryption framework.

Option D. OpenPGP is incorrect because OpenPGP supports encryption and signatures, but it is not the best match where the requirement specifically emphasizes certificate authority-based PKI trust and Outlook-style enterprise certificate validation.

Therefore, the best answer is C. S/MIME.

The correct answer is C. Rogue DHCP Server Attack because the observed impact is that client machines on the LAN begin receiving incorrect network configuration parameters—specifically altered default gateways and DNS server addresses—shortly after Priya connects her laptop. In CEH-aligned LAN attack concepts, a rogue DHCP attack occurs when an attacker introduces an unauthorized DHCP service that responds to DHCP discovery requests faster than the legitimate DHCP server. As a result, endpoints accept the attacker-provided lease options, which can redirect traffic through attacker-controlled infrastructure.

The redirection to “fake login portals hosted on Priya’s machine” is consistent with malicious DHCP option abuse. By supplying a rogue DNS server (or altering DNS-related options), the attacker can resolve internal hostnames (like intranet URLs) to the attacker’s IP, enabling credential harvesting via spoofed portals. By supplying a rogue default gateway, the attacker can position themselves as the network path for victim traffic, enabling man-in-the-middle style interception, traffic manipulation, and session hijacking. The mention of “temporary IP conflicts” further supports rogue DHCP behavior, because an attacker DHCP server can hand out addresses that overlap with the legitimate scope or cause duplicate assignments, producing conflicts and instability.

Why the other options are less accurate: DHCP starvation involves exhausting the legitimate DHCP pool by flooding requests with spoofed MAC addresses, often as a precursor to then standing up a rogue DHCP server. The scenario emphasizes that clients are actively receiving malicious settings (gateway/DNS), which is the hallmark of the rogue server stage rather than starvation alone. DNS cache poisoning targets DNS resolvers/caches and does not by itself cause clients to suddenly obtain new gateway/DNS configurations. Packet sniffing is passive and does not explain clients being reconfigured or redirected.

Therefore, Priya most likely performed a rogue DHCP server attack to reconfigure endpoints and redirect users to phishing portals.

The correct answer is A. --spoof-mac 0.

Nmap supports MAC address spoofing as a firewall-evasion and scan-obfuscation option. The available reference material lists Nmap firewall evasion options and identifies --spoof-mac mac as the option used to spoof the MAC address .

The value 0 tells Nmap to generate a random MAC address. Because the question states that the recorded hardware address changes automatically each time, the random MAC option is the correct match.

Option B. --spoof-mac Dell is incorrect because this selects a MAC address associated with a specific vendor prefix, not the fully random behavior described.

Option C. --spoof-mac 00:01:02:25:56:AE is incorrect because it uses a fixed MAC address. Repeated scans would show the same spoofed address, not a new one each time.

Option D. --spoof-mac Dell 10.10.1.11 is incorrect because it is not the correct Nmap option format for this behavior.

Therefore, the best answer is A. --spoof-mac 0.

CEH identifies spear-phishing as a targeted, context-rich social engineering method tailored to specific individuals or departments. By incorporating accurate insider details, attackers significantly increase trust and likelihood of disclosure.

CEH v13 states that vulnerabilities with a CVSS score ≥ 9.0 are critical and require immediate containment. When remote code execution is possible, the system may already be compromised.

The recommended response is to isolate the affected system, preventing lateral movement, then perform a forensic audit before applying patches. Immediate patching without isolation may alert attackers or destroy evidence.

Thus, option D aligns with CEH incident response best practices.

The correct answer is Deauthentication Attack. CEH wireless security coverage explains that deauthentication attacks abuse 802.11 management frames to force wireless clients to disconnect from an access point. When spoofed deauthentication frames are transmitted, client devices believe they have been instructed to terminate the association and must reconnect manually or automatically. That matches the scenario exactly: carefully crafted management frames are sent, connected laptops immediately lose association, and the disruptions occur only while those frames are being transmitted. Jamming is different because it disrupts wireless communication through radio-frequency interference rather than valid-looking 802.11 management messages. Eavesdropping is passive interception, and an evil twin involves a rogue access point impersonating a legitimate one. CEH materials describe deauthentication attacks as common wireless denial and disruption techniques and also note that they may be used to force reconnects for handshake capture during broader wireless attacks. Because the question focuses on targeted disconnects caused by crafted management frames, the most accurate classification is Deauthentication Attack.