Cryptography Objective Questions and Answers

This cryptography quiz contains carefully curated objective questions with correct answers and clear explanations. It is designed for developers, security learners, and interview preparation, covering modern encryption, hashing, authentication, and security best practices.

Practice Cryptography MCQs with Detailed Explanations

Answer at least 12 questions to submit.

16

Which algorithm is vulnerable to length extension attacks?

Hard
17

What is the key size of AES-256?

Easy
18

Which algorithm is commonly used for key exchange?

Medium
19

What does PBKDF2 stand for?

Medium
20

Which encryption mode is NOT recommended due to pattern leakage?

Medium
21

Which algorithm uses elliptic curves?

Easy
22

What is the main use of Shamir’s Secret Sharing?

Medium
23

Which algorithm is designed to be fast in software?

Medium
24

What does a CSR contain?

Easy
25

Which hashing algorithm produces a 256-bit output?

Easy
26

What is the purpose of Poly1305?

Medium
27

Which cryptographic primitive ensures confidentiality?

Easy
28

Which algorithm is commonly used for file encryption?

Easy
29

What is the main drawback of DES?

Medium
30

Which algorithm is recommended for modern TLS?

Medium