23 Mar - Louiza Papachristodoulou - Online Template Attacks

Side-Channel Attacks (SCA) constitute a constant threat for secure cryptographic implementations. While a cryptographic algorithm is executed,  we can measure the power consumption and electromagnetic emanation of the target device, apply certain signal processing techniques and eventually recover secret information, like private keys. In this talk, after a short introduction to SCA, I am going to present a new powerful attack technique, called Online Template Attacks. The attack is applied on scalar multiplication algorithms for elliptic curves and can be effective to modular exponentiation algorithms as well. Different variations of the attack on two devices and using various distinguishers (Pearson correlation, kNN and SVM from Machine Learning) are going to be presented. Finally, some algorithmic countermeasures against this attack are given.