CWE-306: Missing Authentication for Critical Function - CVE-2016-2354

The CERT Coordination Center has determined that the Lemur BlueDriver does not require a PIN to connect to it via Bluetooth. This allows anyone within Bluetooth range to access standard OBD-II diagnostic information about the car, including gas mileage, Diagnostic Trouble codes, speed, emissions, etc. It also allows an attacker to create a serial connection directly to the CAN (Controller Area Network) bus in the vehicle. Any valid CAN command can be sent to the vehicle. Depending on the vehicle, this may allow attackers to affect safety critical systems such as steering or braking.

The attack is limited to short (Bluetooth) range, but it could be launched from a compromised device inside the car (e.g., cell phone). Depending on the car make and model, impact could range from information disclosure to life-threatening.

Apply an Update
Lemur Vehicle Monitors has released a firmware update to address this vulnerability:

BlueDriver scan tool users can update their sensor Firmware (F/W) by opening
their BlueDriver App and tapping ‘More’ > ‘Update Sensor F/W’ > 'Check for
Updates' and following the instructions.

The latest F/W for BlueDriver limits Bluetooth discoverability to 1 minute
after plug in. This added feature limits discovering (and then pairing) to
your BlueDriver to those who first plug in the sensor.

For clarification, the vendor has stated that discoverability is now limited to only when the device is plugged in, not every time the vehicle is turned on.