Side Auth: Synthesizing Virtual Sensors for Authentication
This work addresses security challenges in embedded systems by leveraging side channels for defender advantage, though it is incremental as it builds on existing sensor and authentication research.
The paper tackles the problem of using sensor side channels beneficially for authentication by synthesizing virtual sensors from existing circuits, demonstrating a proof-of-concept virtual inertial measurement unit from a camera motion side channel and applying it to protect facial recognition against spoofing attacks.
While the embedded security research community aims to protect systems by reducing analog sensor side channels, our work argues that sensor side channels can be beneficial to defenders. This work introduces the general problem of synthesizing virtual sensors from existing circuits to authenticate physical sensors' measurands. We investigate how to apply this approach and present a preliminary analytical framework and definitions for sensor side channels. To illustrate the general concept, we provide a proof-of-concept case study to synthesize a virtual inertial measurement unit from a camera motion side channel. Our work also provides an example of applying this technique to protect facial recognition against silicon mask spoofing attacks. Finally, we discuss downstream problems of how to ensure that side channels benefit the defender, but not the adversary, during authentication.