Ricerc@Sapienza

Latest nanometer CMOS technology nodes have highlighted new issues in security of cryptographic hardware implementations. The constant growth of the static power consumption has led to a new class of side-channel attacks. Common attacks exploiting static power use an univariate approach to recover information from cryptographic engines. In our work, a multivariate approach based on information theoretic security metrics is presented. The temperature-dependence helps to exploit more information leakage from the hardware implementation. Starting from a univariate analysis, mutual information reveals that increasing the working temperature, the information leaked through the static power side channel is increased as well. In this work a multivariate analysis exploiting static power consumption is presented in which the temperature-domain is used to extract more information. The use of information theoretic approach allows to precisely quantify the amount of information that can be leaked from a cryptographic hardware implementation. The perceived information shows taking advantage of the use of more than one temperature, the security level can be decreased. The improvement achieved using the presented approach is demonstrated on a 40 nm CMOS implementation of the Present 80 crypto core.