Researchers have found that hackers can exploit tire pressure sensors, which have been mandatory on all new cars in the United States since the late 2000s, to track a vehicle. All a hacker has to do to track a car’s tire pressure monitoring system (TPMS) is spend a few hundred dollars on some low-cost radio receivers.
According to new research conducted by the IMDEA Networks Institute in Madrid, “Tire Pressure Monitoring System (TPMS) transmissions of modern cars are sent over the air in clear text and entail a unique identifier that does not change over very long periods of time.”
The researchers also learned that hackers could easily scale their efforts to track several thousand cars. This kind of tracking is difficult to recognize and avoid, since these tiny, covert receivers can collect data without drawing any attention and without reading the vehicles’ license plates.
“Most vehicle tracking today uses cameras that need clear visibility and line-of-sight to a car,” the researchers wrote. TPMS tracking is different, they explained. Tire sensors automatically send radio signals that pass through walls and vehicles, allowing small hidden wireless receivers to capture them without detection. Plus, because each sensor broadcasts a fixed, unique ID, the system can recognize the same car repeatedly without reading a license plate.
A vehicle’s TPMS signals are far too easy to hack and track
By matching signals from one automobile’s tires, researchers were able to precisely track cars entering and departing the test area. Regardless of whether the vehicles were in buildings or other blocked locations, the researchers could record TPMS signals from moving automobiles more than 50 meters (about 164 feet) away from the receiver.
The researchers gathered over 6 million signals from about 20,000 vehicles over a 10-week period. Eventually, the researchers were able to compare sensor data to identify trends, such as vehicle type.
The research results indicate that TPMS transmissions can systematically infer potentially sensitive information, such as the driver’s presence, type, weight, or driving pattern.
As a result of their study, the researchers urged “policymakers and car manufacturers to design a more secure and privacy-preserving TPMS for future cars.”