X-Ray Fault Injection in Non-Volatile Memories on Power OFF Devices

For several years, electronic components have taken an increasingly important place in our societies. Their security has become an dominant matter as they can contain sensitive data. To assess their security, new means of fault injection are set up. X-Ray effects on electronic devices have been studied for space applications but only a few recent papers deal with the security point of view. The state of the art shows that X-Ray can more easily have an effect on power off devices than other means of fault injection like laser injection or electromagnetic injection. This article gives experimental results on an X-Ray fault injection campaign on power off microcontrollers dedicated for IoT devices. Some of these X-Ray effects on the Flash embedded non-volatile memory of these microcontrollers highlighted in this study can be reversed performing thermal recuperation. This paper substantiates that the number of faults injected in a memory has an exponential dependency with the total ionizing dose according to a bitset fault model.