Free 312-50v13 Questions Attempt

CEH v13 identifies encrypted communication channels as one of the most common and effective firewall evasion techniques. Firewalls that rely on packet inspection or signature-based filtering often cannot inspect encrypted payloads without SSL/TLS interception capabilities.

By encrypting malicious traffic—using HTTPS, VPN tunnels, or encrypted C2 channels—attackers can bypass firewall rules that inspect packet contents. CEH v13 emphasizes that this technique is widely used in malware communication, data exfiltration, and command-and-control operations.

IP spoofing (Option A) is limited by ingress and egress filtering and is less effective against modern firewalls. Open-source operating systems (Option B) do not inherently evade firewalls. Social engineering (Option D) targets users, not firewalls.

Therefore, Option C is the correct and CEH-aligned answer.

Passive sniffing refers to listening to or capturing network traffic without sending any packets or altering the communication stream. The attacker’s system operates in "promiscuous mode" to monitor all traffic flowing through the network segment. This technique is mostly used in environments like hub-based or unencrypted Wi-Fi networks, where traffic is visible to all systems.

According to the CEH v13 Official Courseware, Module 08: Sniffing, under the subsection "Passive Sniffing", the following capabilities are associated with passive sniffing:

Capturing unencrypted credentials (usernames and passwords)

Identifying protocols, services, IP addresses, and hostnames

Monitoring HTTP sessions, cookies, and other clear-text traffic

Gathering detailed information for fingerprinting and enumeration

Exporting traffic to PCAPs for forensic and offline analysis

However, passive sniffing does not involve any active interference with the traffic. Therefore, actions like “modifying and replaying” packets require an attacker to craft and inject packets into the network — this is considered active sniffing or traffic manipulation, which is out of scope for passive techniques.

Thus:

Option A: Valid for passive sniffing (host discovery via captured traffic)

Option B: Invalid for passive sniffing (requires active traffic manipulation)

Option C: Valid (if data is unencrypted)

Option D: Valid (captures traffic for offline review)

Reference – CEH v13 Official Courseware:

Module 08: Sniffing

Section: “Passive Sniffing vs Active Sniffing”

Study Guide Pages: Usually found under “Types of Sniffing Techniques”

CEH iLabs/Engage Scenarios: Packet capture and Wireshark lab modules

CEH defines ethical hacking as the authorized, structured, and permission-based process of identifying vulnerabilities to strengthen an organization’s security posture. Ethical hackers operate under a signed scope-of-work and follow legal boundaries. Malicious hackers, by contrast, exploit systems without permission, often with harmful or criminal intent. CEH emphasizes that both ethical and malicious hackers may use similar tools, techniques, and methodologies; the distinction lies entirely in authorization, intent, and legality. Ethical hacking is conducted to improve defenses, while malicious hacking targets exploitation, theft, or disruption. Nothing in CEH materials suggests that toolsets or work styles distinguish the two groups; permission and lawful operation remain the central differentiators.

The most plausible reason for the situation is that the secure LDAP connection was not properly initialized due to a lack of ‘use_ssl = True’ in the server object creation. To use secure LDAP (LDAPS), the CEH needs to specify the use_ssl parameter as True when creating the server object with the ldap3 library in Python. This parameter tells the library to use SSL/TLS encryption for the LDAP communication. If the parameter is omitted or set to False, the library will use plain LDAP, which may not be accepted by the target system that only allows secure LDAP connections12. For example, the CEH can use the following code to create a secure LDAP server object:

from ldap3 import Server, Connection, ALL

server = Server('ldaps://', use_ssl=True, get_info=ALL)

connection = Connection(server, user='', password='')

connection.bind()

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

A. The Python version installed on the CEH’s machine is incompatible with the ldap3 library: This option is unlikely because the ldap3 library supports Python versions from 2.6 to 3.9, which covers most of the commonly used Python versions3. Moreover, if the Python version was incompatible, the CEH would not be able to install the library or import it in the code, and would encounter errors before establishing the connection.

C. The enumeration process was blocked by the target system’s intrusion detection system: This option is possible but not very plausible because the CEH was able to establish a connection with the target, which means the intrusion detection system did not block the initial handshake. Moreover, the enumeration process would not affect the response of the target system, but rather the visibility of the results. If the intrusion detection system detected and blocked the enumeration, the CEH would receive an error message or a blank response, not an unexpected response.

D. The system failed to establish a connection due to an incorrect port number: This option is incorrect because the CEH was able to establish a connection with the target, which means the port number was correct. If the port number was incorrect, the CEH would not be able to connect to the target system at all, and would receive a connection refused error.