A new impossible differential attack on SAFER ciphers

This paper presents an improved impossible differential cryptanalysis of SAFER ciphers, which uses the miss-in-the-middle technique developed by Biham et al. We analyze 3.75-round SAFER SK-64,1 using 245245 chosen plaintexts, 238238 bytes memory and 242242 half round computations. Furthermore, the new impossible differential attack on 3.75-round SAFER+/128 uses 278278 chosen plaintexts, 275275 half round computations and 268268 bytes memory. And attack on 3.75-round SAFER++/128 uses 278278 data, 266266 time, and 262262 memory.