One of Amazon's top-selling electronic gun safes contains a critical vulnerability that allows it to be opened by virtually anyone, even when they don't know the password.

The Vaultek VT20i handgun safe, ranked fourth in Amazon's gun safes and cabinets category, allows owners to electronically open the door using a Bluetooth-enabled smartphone app. The remote unlock feature is supposed to work only when someone knows the four- to eight-digit personal identification number used to lock the device. But it turns out that this PIN safeguard can be bypassed using a standard computer and a small amount of programming know-how.

As the video demonstration below shows, researchers with security firm Two Six Labs were able to open a VT20i safe in a matter of seconds by using their MacBook Pro to send specially designed Bluetooth data while it was in range. The feat required no knowledge of the unlock PIN or any advanced scanning of the vulnerable safe. The hack works reliably even when the PIN is changed. All that's required to make it work is that the safe have Bluetooth connectivity turned on.

[...] The vulnerability means that anyone who relies on a VT20i safe to secure valuables should immediately turn off Bluetooth connectivity and leave it off indefinitely. Safes can still be locked and unlocked using a traditional physical key, as well as by owners' fingerprints. Some Amazon customers, however, have complained the fingerprint feature is flawed as well.