Differential fault intensity analysis on PRESENT and LED block ciphers

Abstract

Differential Fault Intensity Analysis (DFIA) is a recently introduced fault analysis technique. This technique is based on the observation that faults are biased and thus are non-uniformly distributed over the cipher state variables. The adversary uses the fault bias as a source of leakage by controlling the intensity of fault injection. DFIA exploits statistical analysis to correlate the secret key to the biased fault behavior. In this work, we show a DFIA attack on two lightweight block ciphers: PRESENT and LED. For each algorithm, our research analyzes the efficiency of DFIA on a round-serial implementation and on a nibble-serial implementation. We show that all algorithms and all implementation variants can be broken with 10 to 36 fault intensity levels, depending on the case. We also analyze the factors that affect the convergence of DFIA. We show that there is a trade-off between the number of required plaintexts, and the resolution of the fault-injection equipment. Thus, an adversary with lower-quality fault-injection equipment may still be as effective as an adversary with high-quality fault-injection equipment, simply by using additional encryptions. This confirms that DFIA is effective against a range of algorithms using a range of fault injection techniques.