📝 Encryption as a Security Tool

Q1. A program copies user input into a local array named buffer[0..63] and then returns from main. Which stack element must the attacker overwrite to hijack execution?

💡 Difficulty: easy | ✅ Correct: B

Q2. Given a buffer of size \(64\) bytes, a shellcode of \(30\) bytes, a saved frame pointer occupying \(8\) bytes, and a return address located immediately after the saved frame pointer, how many NOP bytes must the attacker add to reach the return address?

💡 Difficulty: medium | ✅ Correct: A

Q3. A set‑uid root program contains a stack buffer overflow. Which mitigation alone would stop the injected shellcode from executing, even if the return address is overwritten?

💡 Difficulty: hard | ✅ Correct: D