A Novel Differential Fault Analysis on the Key Schedule of SIMON Family

Abstract

As a family of lightweight block ciphers, SIMON has attracted lots of research attention since its publication in 2013. Recent works show that SIMON is vulnerable to differential fault analysis (DFA) and existing DFAs on SIMON assume the location of induced faults are on the cipher states. In this paper, a novel DFA on SIMON is proposed where the key schedule is selected as the location of induced faults. Firstly, we assume a random one-bit fault is induced in the fourth round key KT−4 to the last. Then, by utilizing the key schedule propagation properties of SIMON, we determine the exact position of induced fault and demonstrate that the proposed DFA can retrieve 4 bits of the last round key KT−1 on average using one-bit fault. Till now this is the largest number of bits that can be cracked as compared to DFAs based on random bit fault model. Furthermore, by reusing the induced fault, we prove that 2 bits of the penultimate round key KT−2 could be retrieved. To the best of our knowledge, the proposed attack is the first one which extracts a key from SIMON based upon DFA on the key schedule. Finally, correctness and validity of our proposed attack is verified through detailed simulation and analysis.