Shabal is a cryptographic hash function submitted by the France-funded research project Saphir to the NIST SHA-3 competition. Saphir brought together research partners, including Cryptolog International, DCSSI, France Telecom, Gemalto, and LIENS, and later, the Saphir2 project added new partners from industry and academia, like EADS SN, INRIA, Sagem Sécurité, and UVSQ.
The Shabal hash function employs a core structure based on a Merkle–Damgård construction with a sponge function, allowing it to handle variable-length input and produce fixed-size hash values efficiently. Although it passed to the second round of the NIST competition, Shabal did not become a finalist due to concerns about potential future attacks related to non-randomness properties with low time complexities.
Details about the specification can be found at https://ehash.iaik.tugraz.at/uploads/6/6c/Shabal.pdf. The original website has since been dismantled.