CCP Cryptography & Information Security 3

Question 1

What is a rainbow table attack?

Accepted Answer

A precomputed table of hash values used to reverse hash functions and recover passwords

Answer

An attack that cycles through every possible key combination

Answer

A side-channel attack that measures electromagnetic emissions

Answer

An attack that exploits collisions in public key certificates

Question 2

How does adding a cryptographic salt to a password before hashing defend against rainbow table attacks?

Accepted Answer

It ensures each password produces a unique hash even if two users have the same password

Answer

It increases the password length, making brute-force infeasible

Answer

It encrypts the hash output using the salt as a symmetric key

Answer

It applies multiple rounds of hashing to slow down attackers

Question 3

What is Perfect Forward Secrecy (PFS) in the context of TLS?

Accepted Answer

A property ensuring that compromise of long-term keys does not expose past session keys

Answer

A guarantee that session keys are never stored on disk

Answer

An algorithm that generates keys resistant to quantum computer attacks

Answer

A protocol extension that prevents man-in-the-middle attacks on TLS handshakes

Question 4

Which security protocol provides end-to-end encryption for email including digital signatures and encryption of message bodies?

Accepted Answer

S/MIME (Secure/Multipurpose Internet Mail Extensions)

Answer

SMTP over TLS (STARTTLS)

Answer

DKIM (DomainKeys Identified Mail)

Answer

SPF (Sender Policy Framework)

Question 5

What is the primary difference between stream ciphers and block ciphers?

Accepted Answer

Stream ciphers encrypt data one bit or byte at a time, while block ciphers encrypt fixed-size chunks of data

Answer

Stream ciphers use asymmetric keys while block ciphers use symmetric keys

Answer

Stream ciphers are used for stored data and block ciphers for network transmission

Answer

Block ciphers are always faster than stream ciphers for large data volumes

Question 6

In cryptography, what does the term 'key derivation function (KDF)' refer to?

Accepted Answer

A function that derives one or more cryptographic keys from a master secret or password

Answer

An algorithm that generates public/private key pairs from random seeds

Answer

A protocol for exchanging keys securely over an untrusted network

Answer

A method for splitting a single key into multiple shares

Question 7

Which attack exploits the mathematical relationship between a public key and its certificate to impersonate a trusted entity?

Accepted Answer

Man-in-the-middle attack using a forged or rogue certificate

Answer

Replay attack

Answer

Brute-force key attack

Answer

Side-channel timing attack