Vehicle Tire Pressure Sensors Enable Silent Tracking

Dark Reading: “Most people would never imagine that the innocuous tire pressure monitoring system (TPMS) in their vehicles could be used to track their movements. But, as with many things digital, it turns out the feature, designed for vehicle safety and maintenance, can also expose unintended signals that enable precisely that capability. Low Cost Vehicle Tracking – A team of researchers from universities in Spain, Switzerland, and Luxembourg recently conducted a study where they deployed a small network of low-cost spectrum receivers, priced at around $100 each, along a road to capture TPMS transmissions from passing vehicles. Their goal was to explore the potentially sensitive information they could infer by analyzing the TPMS transmission data from a set of 12 test vehicles. Over a 10-week period, the researchers gathered more than six million TPMS transmissions from some 20,000 vehicles that used the road. The researchers then used custom-developed algorithms to try and match TPMS signals from each of the different tires on a vehicle to the same car and from there to infer movement of the 12 vehicles in the study.

Our results show that TPMS transmissions can be used to systematically infer potentially sensitive information such as the presence, type, weight or driving pattern of the driver,” the researchers noted in a research paper. Anyone can misuse a TPMS signal to track vehicles and, by extension, the movements of their owners, the researchers said. TPMS sensors — mandated in the US since 2007 — transmit tire pressure readings automatically and at regular intervals whenever a vehicle is in motion. It requires no pairing or authentication and cannot be disabled without compromising the safety function it is designed to provide. The data is sent wirelessly to a receiver module, which is often integrated with the vehicle’s onboard computer or a dedicated TPMS controller. The receiver monitors tire pressure and triggers a dashboard alert if the pressure drops below a predetermined safe threshold…”