Improved Differential Fault Analysis of SOSEMANUK

We present a more efficient differential fault analysis (DFA) attack on SOSEMANUK, a new synchronous software-oriented stream cipher, which is contained in the current eSTREAM Portfolio. In the previous study, it is required around 6144 faults, 2⁴⁸ SOSEMANUK iterations and 2^38.17 bytes storage to recovers the secret inner state of the cipher. We offer an improved attack and show that only around 4608 faults, 2^35.16 SOSEMANUK iterations and 2^23.46 bytes storage are needed under the same or even weaker fault model. The simulation results of the proposed attack show that it takes about 11.35 hours when using a PC.