Wireless networks are being integrated into the modern automobile. The security and privacy implications of such in-car networks, however, have are not well under- stood as their transmissions propagate beyond the con- nes of a car's body. To understand the risks associated with these wireless systems, this paper presents a privacy and security evaluation of wireless Tire Pressure Moni- toring Systems using both laboratory experiments with isolated tire pressure sensor modules and experiments with a complete vehicle system. We show that eaves- dropping is easily possible at a distance of roughly 40m from a passing vehicle. Further, reverse-engineering of the underlying protocols revealed static 32 bit identi- ers and that messages can be.
