🛡️ Free practice test question from: Hashing (Security+)

A collision attack occurs when an attacker can find two different input values that produce exactly the same hash output. In cryptography, a good hash function should make it extremely difficult to find such "colliding" inputs. However, MD5 has been proven to be vulnerable to collision attacks.

A) Preimage Attack: This attack involves finding an input that hashes to a specific output. While relevant to hash functions, the scenario describes creating two different inputs that result in the same hash, not finding a specific input for a given hash.

C) Rainbow Table Attack:
This attack utilizes precomputed tables of hash values to reverse-engineer plaintext inputs from their hashes. It is primarily used for cracking hashed passwords rather than creating hash collisions for digital signatures.

D) Side-Channel Attack: Side-channel attacks exploit indirect information (like timing, power consumption, or electromagnetic leaks) to gain insights into cryptographic operations. This type of attack is unrelated to generating hash collisions for digital signatures.

This scenario illustrates why cybersecurity specialists have moved away from MD5 for security-critical applications. Modern cryptographic practices recommend using more robust hash functions like SHA-256 or SHA-3, which are significantly more resistant to collision attacks.