Snefru (named after the Egyptian Pharaoh Sneferu ) is a cryptological hash function developed by Ralph Merkle that calculates a hash value of 128 or 256 bits for messages of any length.
Eli Biham and Adi Shamir were able to use differential cryptanalysis to show the uncertainty of Snefru's original design by finding message pairs with the same hash value within minutes.
The design was then changed to increase the number of repetitions of the main run of the algorithm .
For safety reasons, it is recommended to use Snefru with eight runs. However, the algorithm is then much slower than other common hash methods.