How Does a ‘Hash Collision’ Relate to Blockchain Security?

A hash collision occurs when two different inputs produce the exact same output hash value. In a blockchain, this would mean two different blocks or transactions could be represented by the same hash, potentially allowing an attacker to substitute a malicious block for a valid one.

While theoretically possible, modern cryptographic hash functions like SHA-256 are designed to make finding a collision computationally infeasible, ensuring the integrity and security of the chain.