Multi-Spot Laser Fault Injection Setup: New Possibilities for Fault Injection Attacks

Fault injection attacks rely on experimental techniques to inject one or several faults into a device during operation. Among these techniques, laser fault injection is known as a powerful one, thanks to its unmatched spatial and temporal precision. So far though, the overwhelming majority of published laser fault injection attacks were performed with only one laser spot. In this article, we present a new multi-spot laser fault injection setup. After a description of the optical system, we highlight its new capabilities against the limitations of existing single-spot laser fault injection setups. We then discuss some intrinsic limitations that this setup has, making it not equivalent to running multiple single-spot setups simultaneously on the same target. We then provide experimental evidence of faults performed with two and four spots which are unfeasible with a single-spot laser fault injection setup. This paves the way for new fault attacks on security and cryptography algorithms that exploit this new type of fault.