My first time at DEF CON, both as an attendee and presenter.
Note this presentation was a Creator Talk.
Abstract
Commercial off-the-shelf autonomous vehicles range from self-driving trucks to military-grade drones. These systems commonly use the PX4 Autopilot flight stack for flight control, navigation, and telemetry. PX4 is a modular stack where logical functions are placed within components. MAVLink is a protocol that facilitates communication between a vehicle and a Ground Control Station. PX4 and its communication facilities are employed in industrial, as well as military environments, where security and correct real-time operation are paramount. This talk will examine how real-time operations and security may be jeopardized by memory corruption and timing-sensitive vulnerabilities in PX4’s communication and logging subsystems. Further, this talk will present a novel time-of-check to time-of-use (TOCTOU) race condition in the MAVLink logging subsystem, MavlinkUlog. This results in a Denial-of-Service where vital commands cannot be sent to the vehicle, sequence tracking is thrown off, and telemetry is unreliable. Through this talk, the unique implications of these vulnerabilities upon autonomous systems deployed in safety-critical environments will be discussed.