BSides Knoxville 2017

One fine summer day, my 1997 Chevrolet Cavalier decided to die. Desperate to save my beloved car, I embarked on a journey to save it.
After some troubleshooting, the problem was narrowed down to the car’s anti-theft system. Even after replacing every component, including the car’s computer, the anti-theft system would still shut off the engine a few seconds after starting it. Rather than give up, I decided to attack the component responsible for making this decision -- the computer.
This talk will discuss my descent into madness as I strove to hack the car’s PCM to disable its anti-theft feature. Everything from physically extracting and dumping the Flash chip holding the PCM’s firmware, to reverse engineering the code, to actually writing a simulator and debugger for a completely unknown device, to finally patching the PCM’s firmware will be described for your entertainment and edification.