Improper Handling of Faults that Lead to Instruction Skips

Hardware can behave unpredictably under certain operating conditions, such as during electrical disturbances or when pushed beyond its normal specifications. These conditions can cause the CPU to skip crucial security instructions, effectively bypassing the logic they were meant to enforce. In practice, this often targets single conditional branch instructions that control security decisions—like password verification or firmware authentication—flipping the intended outcome if skipped. Attackers exploit this by using fault injection techniques to deliberately induce these unstable operating conditions, making instruction skips happen more reliably and frequently than they would naturally. This allows them to manipulate security-critical decision points, such as bypassing authentication checks or altering firmware validation processes.