CCP CCP Cryptography & PKI 2

Question 1

What is a digital signature and how does it work?

Accepted Answer

A hash of the message encrypted with the sender's private key, verifiable with the sender's public key

Answer

A digital signature is created by hashing the message and encrypting the hash with the sender's private key; recipients decrypt it with the sender's public key and compare hashes to verify authenticity and integrity.

Question 2

Which key exchange protocol allows two parties to establish a shared secret over an insecure channel without transmitting the secret itself?

Accepted Answer

Diffie-Hellman (DH) key exchange

Answer

Diffie-Hellman key exchange enables two parties to independently compute the same shared secret using public values, without the secret ever being transmitted.

Question 3

What is the purpose of a Hardware Security Module (HSM) in a PKI deployment?

Accepted Answer

To securely generate, store, and manage cryptographic keys in tamper-resistant hardware

Answer

An HSM is a dedicated hardware device that provides tamper-resistant storage and cryptographic operations for private keys, protecting them from software-based attacks.

Question 4

Which attack involves an adversary intercepting encrypted traffic today with the intention of decrypting it in the future once quantum computers become capable?

Accepted Answer

Harvest-now, decrypt-later (HNDL)

Answer

HNDL attacks involve storing encrypted data captured today and decrypting it once sufficiently powerful quantum computers are available, motivating the transition to post-quantum cryptography.

Question 5

What is a Certificate Transparency (CT) log, and how does it improve PKI security?

Accepted Answer

A publicly auditable append-only log of all issued certificates, enabling detection of misissued or rogue certificates

Answer

CT logs are publicly accessible, append-only records of issued certificates that allow domain owners and security researchers to detect unauthorized or misissued certificates.

(CCP) Certified Cyber Professional Practice Test

(CCP) Certified Cyber Professional Practice Test

CCP CCP Cryptography & PKI 2