Syncing Bluetooth in a vehicle and access text messages from the phone?

Question

If you connect your Bluetooth to a vehicle for music, can the owner of that vehicle download your text messages without your knowledge or can it download the messages that have been erased?

Answer 1

This is not possible without exploiting a vulnerability in your smartphone's Bluetooth drivers (with a "blueborne" attack or similar). The skill set needed to achieve this exploit is very high and this would require a lot of time to develop such an exploit, for little gain most of the time.

You might feel threatened if you are a high-level target from a state actor or a huge unscrupulous corporation, and if the car is owned by a spy. Otherwise, you can feel safe that the scenario you describe does not apply to you.