Ethical Hacking Cryptography and Encryption 1

Question 1

Which hashing algorithm produces a 128-bit hash and is considered cryptographically broken?

Accepted Answer

MD5

Answer

MD5 produces a 128-bit hash but is considered broken for security purposes due to collision vulnerabilities, where two different inputs can produce the same hash value.

Question 2

What is the difference between symmetric and asymmetric encryption?

Accepted Answer

Symmetric uses the same key for encryption and decryption; asymmetric uses a key pair (public/private)

Answer

Symmetric encryption uses one shared key for both encryption and decryption (e.g., AES), while asymmetric encryption uses a mathematically linked public/private key pair (e.g., RSA).

Question 3

Which attack attempts every possible key combination to decrypt encrypted data?

Accepted Answer

Brute force attack

Answer

A brute force attack systematically tries all possible keys or passwords until the correct one is found, becoming impractical as key length increases exponentially.

Question 4

What is 'key exchange' in cryptography and which protocol is most commonly used?

Accepted Answer

Securely establishing a shared secret over an untrusted channel; Diffie-Hellman

Answer

Diffie-Hellman key exchange allows two parties to securely establish a shared secret over an insecure channel without transmitting the actual key, forming the basis of TLS/SSL security.

Question 5

Which cryptographic attack exploits weaknesses in cipher implementation rather than the algorithm itself?

Accepted Answer

Side-channel attack

Answer

Side-channel attacks exploit information leaked from physical implementation (timing, power consumption, electromagnetic emissions) rather than mathematical weaknesses in the algorithm.

Ethical Hacking Practice Test

Ethical Hacking Practice Test

Ethical Hacking Cryptography and Encryption 1