A security countermeasure that mitigates the impact of precomputed hash table attacks by adding a random value to plaintext input is called what?

A security countermeasure that mitigates the impact of precomputed hash table attacks by adding a random value to plaintext input is called what?

• A. salt
• B. pepper
• C. nonce
• D. IV

Answer: (A)

Adding a random value to the input before hashing is done to defeat precomputed hash attacks, and this value is called a salt. The salt makes each hash unique, so even identical passwords produce different hashes. This stops an attacker from using a single rainbow table to crack many passwords at once, because they’d have to generate a new table for every possible salt. The salt is stored with the hash so the system can verify inputs by hashing with the same salt again. Pepper is a secret value added to the input, typically kept separate from the stored hash and not tied to a single user. It doesn’t provide per-user uniqueness like a salt does. A nonce is a value used once to prevent replay attacks, not for password hashing. An initialization vector is used in encryption to randomize ciphertext, not for hashing.

Adding a random value to the input before hashing is done to defeat precomputed hash attacks, and this value is called a salt. The salt makes each hash unique, so even identical passwords produce different hashes. This stops an attacker from using a single rainbow table to crack many passwords at once, because they’d have to generate a new table for every possible salt. The salt is stored with the hash so the system can verify inputs by hashing with the same salt again.

Pepper is a secret value added to the input, typically kept separate from the stored hash and not tied to a single user. It doesn’t provide per-user uniqueness like a salt does. A nonce is a value used once to prevent replay attacks, not for password hashing. An initialization vector is used in encryption to randomize ciphertext, not for hashing.