A timing attack on CUDA implementations of an AES-type block cipher

A timing attack against an AES-type block cipher CUDA implementation is presented. Our experiments show that it is possible to extract a secret AES $128$-bit key with complexity of $2^{32}$ chosen plaintext encryptions. This approach may be applied to AES with other key sizes and, moreover, to any block cipher with a linear transform that is a composition of two types of linear transformations on a substate.