Security News > 2021 > October > How your phone, laptop, or watch can be tracked by their Bluetooth transmissions

Over the past few years, mobile devices have become increasingly chatty over the Bluetooth Low Energy protocol and this turns out to be a somewhat significant privacy risk.

More recently, the US-based researchers explain, software for tracking COVID-19 has used mobile devices as BLE beacons, broadcasting signals in the service of public health.

The boffins looked at at handful of popular mobile devices - ​​iPhone 10, Thinkpad X1 Carbon, MacBook Pro 2016, Apple Watch 4, Google Pixel 5, and Bose QuietComfort 35 wireless headphones - and found they could often successfully fingerprint the physical BLE chip layer.

First, distinguishing devices with the same chipset, like Apple's iPhone, is harder than distinguishing devices with different chipsets.

Third, devices transmit with different power levels, which affects the range at which they can be detected - iPhones evidently broadcast their COVID beacons at a higher power level than Android devices.

"However, we found that simply disabling Bluetooth on some phones will not stop the beacons. For example, on some Apple devices disabling Bluetooth in the Control Center may not stop it from beaconing."

News URL

https://go.theregister.com/feed/www.theregister.com/2021/10/22/bluetooth_tracking_device/