Information, Computer and Network Security Terms Glossary and
Glitch Attack is a method for violating the security of a cryptographic coprocessor (such as a smart card) by disrupting the execution of one or more machine instructions and sequencies. Attacker may inspect the signals generated by the instruction sequence of the circuits and apply an external disturbance at a precise moment when a compare or jump instruction is executing. This effectively blocks the instruction's execution, perhaps bypassing a critical authentication routine. The coprocessor may generate random patterns of sequence to avoid or reduce the risk of the glitch attack.