Fault Sensitivity Analysis Against Elliptic Curve Cryptosystems

In this paper, we present a fault-based security evaluation for an Elliptic Curve Cryptography (ECC) implementation using the Montgomery Powering Ladder (MPL). We focus in particular on the Lopez-Dahab algorithm, which is used to calculate a point on an elliptic curve efficiently without using the y - coordinate. Several previous fault analysis attacks cannot be applied to the ECC implementation employing the Lopez-Dahab algorithm in a straight-forward manner. In this paper, we evaluate the security of the Lopez-Dahab algorithm using Fault Sensitivity Analysis (FSA). Although the initial work on FSA was applied only to an Advanced Encryption Standard (AES) implementation, we apply the technique to the ECC implementation. Consequently, we found a vulnerability to FSA for the ECC implementation using the Lopez-Dahab algorithm.