Related-key cryptanalysis of 3-WAY, Biham-DES,CAST, DES-X, NewDES, RC2, and TEA

Abstract

We present new related-key attacks on the block ciphers 3WAY, Biham-DES, CAST, DES-X, NewDES, RC2, and TEA. Differential related-key attacks allow both keys and plaintexts to be chosen with specific differences [KSW96]. Our attacks build on the original work, showing how to adapt the general attack to deal with the difficulties of the individual algorithms. We also give specific design principles to protect against these attacks.