New GPUThor Rowhammer Defeats ECC on NVIDIA RTX A6000 to Gain Host Root Access

Researchers at the University of Toronto have developed GPUThor, a Rowhammer attack that bypasses ECC memory protection on NVIDIA Ampere-class workstation GPUs (A4000, A5000, A6000) to achieve denial-of-service and privilege escalation. The attack exploits non-uniform hammering patterns to induce bit flips, leading to silent data corruption and ultimately root access on the host system. While ECC still provides a barrier, it’s not a foolproof defense, and a complete fix requires stronger in-DRAM defenses.