Characterizing Power Distribution Attacks in Multi-User FPGA Environments

Multi-tenant FPGAs that contain circuits from multiple users are emerging as a new usage model in cloud and embedded computing environments. Interactions between untrusting tenant applications in an FPGA can enable new security exposures and the risk of side channel attacks or fault injection. In this work, we investigate the ability for aggressive power consumption of one application to disturb the power network to an extent that causes delay faults in a second application on the same FPGA. In particular, we identify the mechanisms by which the supply voltage is disturbed by the attack, and we characterize the magnitude of the disturbance as a function of time, power consumed by attacker, and position of the victim relative to the attacker. We highlight strategies that can be used to mitigate attacks, including low-cost monitoring circuits that can identify the source of an attack so that the attacker's use of the FPGA can be revoked.