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📝 Password vulnerabilities
📖 From Operating System • 15. Security • 18 questions available
Practice MCQs for Password vulnerabilities. Test your knowledge with carefully crafted questions across easy, medium, and hard difficulty levels.
🔄 Last updated: 2026-07-27
📝 Sample Questions
Q1. What is a polymorphic virus?
🔹 A. A virus that encrypts its code before execution
🔹 B. A virus that changes its code each time it infects a system
🔹 C. A virus that hides by modifying system calls
🔹 D. A virus that spreads through macro scripts
💡 Difficulty: easy | ✅ Correct: B
Q2. How does a stealth virus evade detection by modifying system calls?
🔹 A. It changes the read system call to return the original file content
🔹 B. It encrypts its payload before execution
🔹 C. It installs itself in the interrupt‑handler chain
🔹 D. It replaces the boot sector with malicious code
💡 Difficulty: medium | ✅ Correct: A
Q3. Explain how the logic bomb component of a boot virus can affect system stability beyond initial infection.
🔹 A. It triggers at a specific date causing a system crash
🔹 B. It hides the original boot sector
🔹 C. It copies the boot sector to an unused location
🔹 D. It increases the visible memory limit
💡 Difficulty: hard | ✅ Correct: A
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