3 - 6: Cryptanalytic Attacks

Question 1

Brute-force attack

Answer 1

Attacker makes repeated guesses at an encryption key until they guess the correct value. AKA known ciphertext attacks.

Question 2

Keyspace

Answer 2

List of possible encryption keys. For example, the English alphabet has a keyspace of 25.

Question 3

Knowledge-based attacks

Answer 3

A category of attacks where an attacker combines information with other cryptanalytic techniques

Question 4

Frequency analysis attack

Answer 4

Attacker detects patterns in the ciphertext, including statistics and common letters, to guess a key

Question 5

Known Plaintext attack

Answer 5

Attacker has access to an unencrypted message, allowing them to check their knowledge of a cryptographic key

Question 6

Chosen Plaintext attack

Answer 6

Attacker can create an encrypted message of their choice

Question 7

Birthday attack

Answer 7

Attacker finds two inputs with the same hash values

Question 8

Longer keys require…

Answer 8

…more computing power

Question 9

The longer a key is, the more….

Answer 9

….resistant it is to brute-force

Question 10

Entropy

Answer 10

A value representing how predictable an algorithm is. The higher the value, the less predictable the algorithm

Question 11

Downgrade attack

Answer 11

Attacker tricks two communicating parties into not encrypting or reducing the level of encryption used