Security News > 2023 > November > Weak session keys let snoops take a byte out of your Bluetooth traffic

The attacks force the creation of weak session keys, which are used when paired Bluetooth devices try to establish a secure communication channel.

Weak keys can be easily broken, allowing the eavesdropper to hijack sessions and snoop on victims' conversations, data, and activities carried out over Bluetooth.

"The attacks exploit two novel vulnerabilities that we uncover in the Bluetooth standard related to unilateral and repeatable session key derivation."

The BLUFFS code repo contains Arm code patches and an attack-checking tool that takes packet capture files and isolates Bluetooth sessions to calculate session keys and detect BLUFFS attacks.

Antonioli has proposed protocol-level countermeasures involving three extra Link Manager Protocol packets and three extra function calls that vendors can implement while awaiting a Bluetooth specification revision that makes session establishment more secure.

The notification advises those implementing Bluetooth to configure their systems to reject connections with weak keys.

News URL

https://go.theregister.com/feed/www.theregister.com/2023/11/30/bluetooth_bluffs_attacks_are_no/