A length extension attack is a type of cryptographic exploit that takes advantage of certain properties of hash functions, specifically those that use the Merkle-Damgård construction. This attack allows an adversary to compute the hash of a message without knowing the original message but with knowledge of its hash, enabling the attacker to append additional data and compute a new valid hash. This vulnerability is particularly concerning for hash functions that are not resistant to length extension, as it undermines the integrity and authenticity of the data.
congrats on reading the definition of Length Extension Attack. now let's actually learn it.