SSCP Cryptography & PKI 2

Question 1

Which cryptographic attack involves an adversary obtaining ciphertext-plaintext pairs of their choosing to deduce the key?

Accepted Answer

Chosen-plaintext attack

Answer

A chosen-plaintext attack lets the adversary select arbitrary plaintext and observe corresponding ciphertext, making it stronger than a known-plaintext attack.

Question 2

What is the primary purpose of a Certificate Revocation List (CRL)?

Accepted Answer

To publish certificates that are no longer valid before expiration

Answer

A CRL is a signed list published by a CA that identifies certificates revoked prior to their expiration date.

Question 3

In asymmetric cryptography, what operation does the sender perform to ensure non-repudiation when signing a message?

Accepted Answer

Encrypts with the sender's private key

Answer

Signing with the sender's private key creates a digital signature only that entity could produce, ensuring non-repudiation.

Question 4

Which mode of AES operation produces ciphertext blocks that depend on all preceding plaintext blocks?

Accepted Answer

CBC (Cipher Block Chaining)

Answer

CBC XORs each plaintext block with the previous ciphertext block before encryption, chaining all blocks together.

Question 5

What does the term 'key escrow' mean in cryptography?

Accepted Answer

Storing a copy of encryption keys with a trusted third party

Answer

Key escrow involves depositing cryptographic keys with a trusted third party so they can be retrieved under authorized circumstances.

(SSCP) Systems Security Certified Practitioner Exam Practice Test

(SSCP) Systems Security Certified Practitioner Exam Practice Test

SSCP Cryptography & PKI 2