Learn how to attack and defend Vehicle Diagnostics Adapters (VDAs) in this DEF CON 31 security talk that explores hardware reverse engineering, firmware analysis, and automotive cybersecurity. Dive into the technical process of enumerating components, accessing UART interfaces, extracting and modifying firmware, and understanding update procedures for VDA devices commonly left behind in vehicles. Master defensive techniques including Autotomic Binary Reduction (ABR), RTOS firmware reverse engineering, and feature entry point identification. Explore real-world applications through the Cyber Truck Challenge workshop using OFRAK and VDA, while examining DC30 CHV CTF challenges. Gain practical insights into both offensive and defensive aspects of automotive security, with a focus on protecting these often overlooked vehicle components.