User credentials were captured from a database during an assessment and cracked using rainbow tables. Based on the ease of compromise, which of the following algorithms was MOST likely used to store…

MD5 is a fast, unsalted hashing algorithm, and passwords hashed with MD5 are highly susceptible to cracking using rainbow tables. Rainbow tables pre-compute hashes for common passwords, and MD5's speed makes it easy to compare hashes against these tables efficiently, especially without salting.

bcrypt is a strong, slow, and salt-aware hashing algorithm specifically designed to be resistant to rainbow table attacks and brute-force attacks by increasing the computational cost of hashing.

SHA-1, like MD5, is a fast hashing algorithm, but its hashes are still more computationally expensive to crack with rainbow tables compared to MD5, and its resistance significantly improves with salting.

PBKDF2 (Password-Based Key Derivation Function 2) is a key derivation function designed to make brute-force and rainbow table attacks computationally expensive by repeatedly applying a pseudorandom function, making it resistant.