One of the features of Bluetooth connections is that when you move within range of a previously paired device, it should reconnect almost immediately. This is useful when you have wireless headphones, speakers, or are trying to connect to your car’s infotainment system, but unfortunately, it seems that a flaw in this system has put billions of devices at risk.
Discovered by researchers at Purdue University and known as BLESA (Bluetooth Low Energy Spoofing Attack), it seems that this vulnerability exploits the reconnecting of previously paired devices. Ideally, when devices reconnect with each other, they should re-check each other’s cryptographic keys.
However, due to the language of the protocol, it was discovered that this reauthentication is not mandatory and is apparently optional. Even when applied, it could also be circumvented. This means that in theory, attackers might be able to spoof the connections of previously connected devices, thus allowing them to trick users into connecting to a completely different device and intercept their traffic and conduct malicious attacks.
The good news is that based on what the researchers found, Windows devices are apparently immune to this attack, and so are Apple’s devices as the company had patched the flaw back in May. However, IoT devices, Android devices, and Linux-based laptops are at risk, but hopefully manufacturers will issue updates to address this problem soon.