First practical side-channel attack to defeat point randomization in secure implementations of pairing-based cryptography
Résumé
The field of Pairing Based Cryptography (PBC) has seen recent advances in the simplification of their calculations and in the implementation of original protocols for security and privacy. Like most cryptographic algorithms, PBC implementations on embedded devices are exposed to physical attacks such as side channel attacks, which have been shown to recover the secret points used in some PBC-based schemes. Various countermeasures have consequently been proposed. The present paper provides an updated review of the state of the art countermeasures against side channel attacks that target PBC implementations. We especially focus on a technique based on point blinding/randomization. We propose a collision based side-channel attack against an implementation embedding the point randomization countermeasure. It is, to the best of our knowledge, the first proposed attack against this countermeasure used in the PBC context and this raises questions about the validation of countermeasures for c omplex cryptographic schemes such as PBC. We also discuss about ways of thwarting our attack
