Critical Bluetooth vulnerability gives hackers full access

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A new vulnerability has been found in the Bluetooth wireless standard. Hackers can exploit it to connect to devices remotely in any given area and access phone apps. The flaw has since been named Blurtooth and was described in detail by the Bluetooth SIG industry body that oversees the standard development. 

Currently, there are no patches available. Bluetooth is present in billions of devices worldwide. They range from smartphones to IoT (Internet of Things) devices. In the consumer setting, people use it to pair with things like wireless earbuds in short ranges. Bluetooth also supports long-range data transfer over several hundred feet.

A neat trick

With a range that long, hackers can exploit the Blurtooth flaw to launch an attack. The flaw is a result of the way Bluetooth verified the security of connections. Typically, the users have to approve a connection request before their devices get linked.

Blurtooth makes it possible for one to circumvent this precaution step.

A hacker can configure their malicious systems to impersonate a Bluetooth device that has already been approved by the user, such as wireless earbuds, and gain access to the victim’s machine.

Limited threat

Blurtooth attacks rely on the vulnerability in a security feature known as CTKD. Usually, the feature is used in encryption. However, the hacker can hijack the authentication key of a device you previously approved and impersonate a legitimate endpoint, circumventing the need to ask.

Because of the limited wireless range of the Bluetooth Standard, the threat is somewhat limited. The widespread use is the only issue here, as it could mean that endpoints that could be potentially vulnerable exist anywhere phones exist.

The flaw was found by researchers at Switzerland’s EPFL École Polytechnique Fédérale de Lausanne and Purdue University.