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

The CEH Cryptanalysis module describes differential cryptanalysis as an attack that studies the relationship between differences in input and resulting differences in output to recover secret keys.

Option A precisely matches this definition.

Option B relies on execution timing.

Option C requires ciphertext manipulation.

Option D exhaustively tests keys.

CEH lists differential cryptanalysis as a foundational theoretical attack.

According to CEH v13 Network Scanning Techniques, a FIN scan is a stealth scanning method that sends TCP packets with only the FIN flag set. Its behavior relies on RFC 793, which specifies that closed ports must respond with a TCP RST, while open ports should silently drop the packet.

However, modern firewalls, IDS/IPS systems, and hardened TCP/IP stacks often filter or silently drop FIN packets regardless of port state. Therefore, when a FIN scan results in no response from a large number of ports, it does not conclusively indicate that the ports are open. Instead, CEH v13 stresses that this behavior commonly points to packet filtering by firewalls or security controls.

Option A is incorrect because a lack of response does not definitively mean ports are closed. Option B is an overreaction; stealth scan anomalies alone do not indicate a breach. Option C is unlikely because congestion would impact multiple protocols, not selectively suppress FIN responses.

CEH v13 recommends that when FIN scans produce ambiguous results, analysts should correlate findings using additional scan types (such as SYN scans) and investigate firewall rules and filtering behavior. Thus, option D is the most accurate interpretation and aligns with CEH guidance.

Fingerprinting the running service is the most appropriate technique because the strongest indicator in the scenario is inconsistent protocol behavior and error responses that do not match a legitimate production database service. In CEH reconnaissance guidance, honeypots and decoy systems often emulate common services but may implement only partial protocol stacks or simplified responses. This can lead to anomalies such as incorrect banner strings, malformed or generic error messages, unsupported command handling, unusual protocol negotiation, or responses that do not align with the claimed software version. By fingerprinting, Mia compares observed behavior against expected behavior for the genuine service, including version-specific quirks, command sets, response codes, and timing patterns for particular requests.

In practice, service fingerprinting involves interacting with the service using legitimate and edge-case requests, validating banners and headers, and correlating results with known signatures from real implementations. If the server claims to be a specific database or application service but reacts in ways that real deployments would not, it suggests emulation, instrumentation, or deception typical of honeypots designed to log attacker activity.

Analyzing response time can help, because some honeypots respond too quickly or with uniform timing, but timing alone is less definitive than protocol inconsistencies. MAC address analysis is not reliable for identifying honeypots and is often not visible beyond the local segment. Analyzing system configuration and metadata usually requires deeper access than reconnaissance and is not the primary method when the clue is protocol-level mismatch. Therefore, fingerprinting the running service best fits the observed symptoms.

QUBB ESTION NO: 25 [Mobile Platform and IoT Hacking]

Javier Ruiz from CyberFortress Solutions is tasked with auditing the mobile security practices of Apex Financial Services, a financial firm in Houston, Texas. During a covert penetration test, Javier targets employees ' personal smartphones used to access corporate financial systems. He exploits a vulnerability by installing a malicious app that bypasses access controls, granting him unauthorized entry to sensitive financial data because the devices lack a specific security measure to restrict app access. Based on this vulnerability, which BYOD security guideline is most likely missing in Apex Financial Services ' policy?

A. Review permissions requested by apps before installing them

B. Set passwords for apps to restrict others from accessing them

C. Enforce automatic device locking or implement biometric authentication

D. Use encryption mechanisms to store data

Answer: A

The most likely missing BYOD guideline is reviewing application permissions before installation. In CEH mobile security guidance, a major risk in BYOD environments is the introduction of untrusted or malicious applications that abuse the mobile permission model to access corporate data, intercept authentication tokens, read storage, capture keystrokes via accessibility services, or communicate externally. When users install apps without scrutinizing requested permissions, they may unknowingly grant excessive privileges that enable data theft or access-control bypass, especially if the app leverages OS weaknesses or misconfigurations.

The scenario states Javier “installs a malicious app that bypasses access controls” and gains access to sensitive financial data because devices “lack a specific security measure to restrict app access.” This maps directly to a policy gap around controlling and validating apps and their permission requests. CEH emphasizes that organizations should reduce attack surface by limiting app privileges, avoiding sideloading from untrusted sources, and enforcing least privilege through user awareness and enterprise controls such as MDM application allowlisting and permission governance. Reviewing permissions is the user-facing guideline that prevents employees from granting dangerous access (for example, SMS, storage, contacts, accessibility, device admin, or VPN configuration permissions) that can enable credential theft or unauthorized data access.

Option B adds an extra layer for local access but does not stop a malicious app with granted permissions from accessing corporate data. Option C helps if a device is physically stolen, but it does not prevent malicious apps already running under the user context. Option D protects data at rest, yet a malicious app can still exfiltrate data once it is decrypted and accessed by the user session. Therefore, permission review is the most directly relevant missing BYOD guideline.

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.