CREST CREST Cryptography & Data Protection 3

Question 1

What does Perfect Forward Secrecy (PFS) guarantee in a TLS session?

Accepted Answer

Compromise of the long-term private key does not expose past session keys

Answer

The server certificate cannot be forged

Answer

Encrypted sessions cannot be replayed

Answer

The client is always authenticated

Question 2

Which standard defines requirements for key management and cryptographic modules in the US?

Accepted Answer

FIPS 140-2

Answer

ISO 27001

Answer

PCI DSS

Answer

NIST SP 800-53

Question 3

What is the purpose of salting a password before hashing it?

Accepted Answer

To prevent rainbow table and dictionary attacks

Answer

To speed up password verification

Answer

To ensure the hash length is longer

Answer

To encrypt the hash with a key

Question 4

In a CREST assessment, discovering that an application uses ECB mode for AES encryption is significant because:

Accepted Answer

Identical plaintext blocks produce identical ciphertext blocks, leaking patterns

Answer

ECB is not supported by OpenSSL

Answer

ECB mode doesn't support 256-bit keys

Answer

ECB requires a public/private key pair

Question 5

What type of cryptographic attack requires finding two different inputs that produce the same hash output?

Accepted Answer

Collision attack

Answer

Preimage attack

Answer

Length extension attack

Answer

Key recovery attack

Question 6

Which encryption approach is most appropriate for protecting data stored in a database column containing credit card numbers?

Accepted Answer

Column-level encryption with AES

Answer

Full-disk encryption only

Answer

Base64 encoding

Answer

XOR with a static key