Transduction Shield: A Low-Complexity Method to Detect and Correct the Effects of EMI Injection Attacks on Sensors

ABSTRACTThe reliability of control systems often relies on the trustworthiness of sensors. As process automation and robotics keep evolving, sensing methods such as pressure sensing are extensively used in both conventional systems and rapidly emerging applications. The goal of this paper is to investigate the threats and design a low-complexity defense method against EMI injection attacks on sensors. To ensure the security and usability of sensors and automated processes, we propose to leverage a matched dummy sensor circuit that shares the sensor's vulnerabilities to EMI but is insensitive to legitimate signals that the sensor is intended to measure. Our method can detect and correct corrupted sensor measurements without introducing components or modules that are highly complex compared to an original low-end sensor circuit. We analyze and evaluate our method on sensors with EMI injection experiments using different attack parameters. We investigate several attack scenarios, including manipulating the DC voltage of the sensor output, injecting sinusoidal signals, white noises, and malicious voice signals. Our experimental results suggest that, with relatively low cost and computation overhead, the proposed method not only detects the attack but also can correct corrupted sensor data to help maintain the functioning of systems based on different kinds of sensors in the presence of attacks.