Technically you could exploit anything, you just have to find the exploit. I’m not sure what you’re asking here, but BLE does require some user interaction to be activated and/or accept data transfer requests with an app receiving data packets through a supposedly secure OS. If you could somehow make the stack avoid the user, or find a specific app which has an overflow upon receiving a malicious request, you’d have an exploit. Or if you find an issue in the underlying radio. But if properly implemented without bugs, and everybody cleans their variables, exploits will be difficult.