Cryptographic Attacks

Question 1

Birthday attack

Answer 1

Exploit the mathematics behind the birthday problem in probability theory to cause a collision (hash type attack)

Question 2

Side channel attack

Answer 2

Is any attack based on information gained from implementation of a computer system, rather than weaknesses in the implemented algorithm itself, monitoring cpu cycles, power consumption, radiation and timing to break the cryptosystem

Question 3

Broken

Answer 3

Means that algorithm and/or key lenght is exploitable (use of 802.11 or DES encryption)

Question 4

Depreciated

Answer 4

Means that the use of algorithm and key length is allowed, but the user must accept the risk/weakness

Question 5

Depreciated

Answer 5

Means that the use of algorithm and key length is allowed, but the user must accept the risk/weakness

Question 6

Frequency analysis attack

Answer 6

Cryptovariable (key)attack, analyses patterns of frequencies (specific letters) in encrypted messages to deduce information about underlying plaintext or key used to encrypt the message

Question 7

Rainbow tables

Answer 7

Publicly available tables of precomputed hashes that can be used to quickly attack and crack password hashes

Question 8

Brute force

Answer 8

Cryptovariable (key) attack, every possible key is tested (online/offline) until a key is discovered and that successfully decrypts the ciphertext . Brute force attacks are limited by Workfactor and discovery

Question 9

Collision

Answer 9

Hash attack, uses mathematical technique to force two inputs into producing the same hash value. The hash metod used cannot be relied on any more to identify different data

Question 10

Downgrade attack

Answer 10

Common and strong attack, it forces degradation to lower-quality crypto model. Attacker exploits the lesser security control from TLS to SSL, from HTTPS to http

Question 11

Dictionary attack

Answer 11

Cryptovariable (key) attack, a list of known keys are tested (common word list)

Question 12

Pass the hash

Answer 12

Hash attack, attackers can use captured hashed credentials from one machine to successfully gain control of another machine

Question 13

Timming attack

Answer 13

Exploits the fact that different computations take different time to compute on the processor, it the encryption takes time it indicates that the secret key is long

Question 14

Ransomware

Answer 14

Is a form of malware designed to encrypt files on a device and rendering them to unusable. Adds an extension to the encrypted files (.aaa,.micro) to show that the files have been encrypted. The extension is unique to ransomware. After finishing encryption ransomware displays the file with instruction how to pay to receive decryption key.