Differential fault analysis on the lightweight block cipher plug‐in plug‐out

In recent years, many lightweight block ciphers were proposed to provide security for resource‐constrained environments such as Internet of Things (IoT). PIPO, which stands for “plug‐in plug‐out”, is just a lightweight bit‐sliced block cipher offering excellent performance in 8‐bit AVR software implementations. In fact, PIPO owns 64‐bit input and output, 128‐bit secret key. In this article, we consider the differential fault analysis (DFA), a typical side‐channel attack, on the PIPO cipher. More concretely, for the first time, we apply the mixed attack model, which considers the DFA on the encryption state and key schedule simultaneously, to recover PIPO's 128‐bit master key. The theoretical analysis shows that, in average, after injecting 4‐byte faults, the complexity of obtaining the master key reduces from 2128 reduces to 214. In fact, this attack model alleviates the assumption on attacker than the bit‐injection case. It should be noted that our analysis also holds for other bit‐sliced block ciphers. Finally, the simulations show that our proposed DFA on PIPO cipher is rather practical.