Linear and Differential Cryptanalysis of SHA-256

The one-way hash function plays an important role in digital signatures and message authentication from the viewpoint of security. No effective attacking method has been discovered to the algorithm of hash function standard. In this study, we tried to attack SHA-256 in encryption mode using linear and differential cryptanalysis to solve a private key. We deduced that an estimate of the private key would require huge known and chosen plaintexts in both linear and differential cryptanalysis, and that it would be difficult to decipher SHA-256 in view of the required computation.