Nowadays, security is one of the foremost concerns as the confidence in a system is mostly dependent on its ability to protect itself against any attack. The area of Electromagnetic Fault Injection (EMFI) wherein attackers can use electromagnetic (EM) pulses to induce faults has started garnering increasing attention. It became crucial to understand EM attacks and find the best countermeasures. In this race to find countermeasures, different researchers proposed their ideas regarding the generation of EM attacks and their detection. However, it is difficult to see a universal agreement on the nature of these attacks.

In this work, we take a closer look at the analysis of the primary EMFI fault models suggested earlier. Initial studies had shown that EM glitches caused timing violations, but recently it was proposed that EM attacks can create bit sets and bit resets. We performed a detailed experimental evaluation of the existing detection schemes on two different FPGA platforms. We present their comparative design analysis concerning their accuracy, precision, and cost. We propose an in situ timing sensor to overcome the disadvantages of the previously proposed detection approaches. This sensor can successfully detect most of the electromagnetic injected faults with high precision. We observed that the EM attack behaves like a localized timing attack in FPGAs which can be identified using the in situ timing sensors.