Exactprep 312-50v13 Questions

Ransomware encrypts user data and extorts payment for restoration. CEH covers ransomware as a major threat in system hacking, highlighting encryption-based extortion as its defining behavior.

A Stealth or Tunneling Virus is designed specifically to evade detection by antivirus software and system monitoring tools. These viruses work by intercepting and modifying the operating system’s service call interrupts (such as INT 13h and INT 21h in DOS systems), which are used to access files or system services.

By hooking into these interrupts, the virus can return clean or forged data to antivirus scanners, thus hiding its malicious presence from detection tools.

Tunneling viruses may also operate at a lower level to evade even more advanced antivirus detection methods, making them particularly dangerous and hard to detect.

Reference – CEH v13 Official Study Guide:

Module 6: Malware Threats

Section: Types of Viruses

Quote:

“Tunneling viruses attempt to avoid detection by antivirus programs by installing themselves in the interrupt handler chain. These viruses intercept operating system calls to conceal their activities.”

Incorrect Options Explained:

A. Macro viruses target applications like Microsoft Word/Excel and use embedded macros, but do not alter service call interrupts.

C. Cavity viruses insert code into empty spaces in files without changing the file size but do not modify interrupts.

D. Polymorphic viruses mutate their code to avoid signature-based detection but do not typically interfere with system interrupts directly.

According to the CEH Vulnerability Assessment and Incident Response modules, vulnerabilities with high CVSS scores and potential RCE must be treated as active threats.

CEH best practices recommend:

Immediate containment (network isolation)

Investigation and impact analysis

Patch application

Recovery

Option D follows the CEH incident response lifecycle precisely.

Option C is incomplete without containment.

Options A and B are unsafe.

CEH emphasizes containment before remediation.

CEH courseware describes rootkits as specialized malware designed to conceal their presence while providing persistent, unauthorized access to system-level functions. Rootkits typically modify low-level components of the operating system—such as kernel modules, drivers, or system processes—to hide files, processes, registry keys, and network connections. Their primary purpose is to grant attackers administrative privileges without triggering alerts, making them extremely stealthy and dangerous. CEH emphasizes that rootkits often accompany other malware to maintain long-term control after initial compromise. In contrast, viruses replicate by attaching to files, keyloggers record keystrokes but do not hide system-level access, and ransomware encrypts data rather than conceals operations. The defining characteristics in this scenario—cloaking activity, providing admin-level control, persisting undetected—are directly aligned with rootkit behavior as described in CEH training material.