In cryptography, a collision attack on a cryptographic hash tries to find two arbitrary inputs that will produce the same hash value, i.e. a hash collision. In contrast to a preimage attack, neither the hash value nor one of the inputs is specified.
There are roughly two types of collision attacks:
- Collision attack
- Find two arbitrary different messages m1 and m2 such that hash(m1) = hash(m2).
- Chosen-prefix collision attack
- Given two different prefixes p1, p2 find two appendages m1 and m2 such that hash(p1 ∥ m1) = hash(p2 ∥ m2) (where ∥ is the concatenation operation).
Read more about Collision Attack: Classical Collision Attack, Chosen-prefix Collision Attack, Attack Scenarios
Famous quotes containing the words collision and/or attack:
“I know my fate. One day my name will be tied to the memory of something monstrous—a crisis without equal on earth, the most profound collision of conscience, a decision invoked against everything that had previously been believed, demanded, sanctified. I am no man, I am dynamite!”
—Friedrich Nietzsche (1844–1900)
“If you attack the establishment long enough and hard enough, they will make you a member of it.”
—Art Buchwald (b. 1925)