The carwhisperer project intends to sensibilise manufacturers of carkits and other Bluetooth appliances without display and keyboard for the possible security threat evolving from the use of standard passkeys.

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Once the connection has been successfully established, the carwhisperer binary starts sending audio to, and recording audio from the headset. This allows attackers to inject audio data into the car. This could be fake
traffic announcements or nice words. Attackers are also able to eavesdrop conversations among people sitting in the car.

This could be fun. :)