Physics-based Security Analysis of Controller Area Network Protocols

Abstract

A contemporary automobile is equipped with many sensors and actuators that are controlled by electronic units. These electronic units are connected via wired bus networks, and data for controlling the automobile is exchanged among the electronic units using in-vehicle network protocols. The in-vehicle network protocols were designed to be isolated from external networks, and they do not encrypt data or authenticate messages as a consequence. To provide a higher quality of service, such as traffic information or over-the-air software updates, electronic units that can be connected to the external networks are installed in the contemporary automobile. These electronic units with outward-facing interfaces act as attack surfaces to in-vehicle networks and other electronic units. In this dissertation, we identify vulnerabilities of in-vehicle network protocols such as the Controller Area Network (CAN) and existing intrusion detection systems. In order to enhance the security of the CAN protocol from these vulnerabilities, we develop software and hardware-based defense mechanisms that can detect attacks by exploiting timing, voltage, and motion information, where the hardware-based defense mechanism can also mitigate these attacks. We implement the attacks and demonstrate that the proposed defense mechanisms can effectively detect and mitigate the attacks using a CAN bus testbed and a real vehicle.