Side-channel leakage from sensor-based countermeasures against fault injection attack

Abstract

In laser fault injection, an attacker injects laser to a chip implementing cryptography and exploits a fault to attack the cryptography. A promising approach to counteract fault injection attack is to detect an attempt of fault injection using sensors. In such a sensor-based countermeasure, a sensor detects a physical anomaly and raises an alarm so that the system can react to the attempt of an attack properly. Among them, the bit-flip detector, that detects a short-circuit current induced by a laser fault injection, is actively studied as an efficient realization. In this paper, we give the first security evaluation of the bit-flip detector. We show that an attacker can reveal an internal state by observing how the sensor reacts to laser fault injection. The leakage leads to a variant of probing attack that is feasible non-invasively. We also propose a new cryptanalytic technique that efficiently exploit the leakage to attack AES.