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A Belgian security investigator has revealed a technique to overwrite and hijack the firmware of Tesla Model X key fobs, letting him steal any car that is not running on the latest software update.
The attack, which only takes a few minutes to perform and requires low-priced gear, was put together by Lennert Wouters, a PhD student at the Computer Security and Industrial Cryptography (COSIC) group at the Catholic University of Leuven (KU Leuven) in Belgium.
In a report, Wouters said this third attack works due to a fault in the firmware update process of Tesla Model X key fobs.
The fault can be taken advantage of using an electronic control unit (ECU) rescued from an older Model X vehicle, which can be effortlessly attained online on sites like eBay or any stores or forums selling used Tesla car parts.
Wouters said invaders can adapt the older ECU to deceive a victim’s key fob into believing the ECU belonged to its paired vehicle and then push a hateful firmware update to the key fob via the BLE (Bluetooth Low Energy) protocol.
“As this update mechanism was not properly secured, we were able to wirelessly compromise a key fob and take full control over it,” Wouters said. “Subsequently we could obtain valid unlock messages to unlock the car later on.”
