On the Exact Relationship Between the Success Rate of Template Attack and Different Parameters

Abstract

In practice, the Template Attack (TA) is widely accepted as the strongest side channel attack, and it is used to evaluate the physical security of crypto devices in practice. In TA, different statistical tools, such as the Euclidean distance (ED) and the Mahalanobis distance (MD), can be used to recover the secret key used by the target device. In practice, values of different parameters influence the key-recovery efficiency of TA. However, until now, the exact relationship between the success rate (SR) of TA and different parameters is not very clear. Therefore, in order to accurately evaluate the physical security of crypto devices with TA, evaluators need to vary values of different parameters and empirically evaluate the SR of TA in different cases. Considering that both the computational complexity and the measurement complexity of the empirical evaluation are high, this may induce unnecessary evaluation overhead and make the evaluation period long. In light of this, in this paper, the exact relationship between the SR of TA and values of different parameters is theoretically analyzed, and the soundness of the theoretical analysis is empirically verified in both simulated and real scenarios. Then, by setting the values of different parameters, the SR of TA can be accurately and efficiently estimated. Overall, this contribution may help evaluators to efficiently evaluate the physical security of crypto devices with TA in practice.