Improved side-channel analysis attacks on xilinx bitstream encryption of 5, 6, and 7 series

Abstract

Since 2012, it is publicly known that the bitstream encryption feature of modern Xilinx FPGAs can be broken by side-channel analysis. Presented at CT-RSA 2012, using graphics processing units (GPUs) the authors demonstrated power analysis attacks mounted on side-channel evaluation boards optimized for power measurements. In this work, we extend such attacks by moving to the EM side channel to examine their practical relevance in real-world scenarios. Furthermore, by following a certain measurement procedure we reduce the search space of each part of the attack from 232 to 28, which allows mounting the attacks on ordinary workstations. Several Xilinx FPGAs from different families – including the 7 series devices – are susceptible to the attacks presented here.