Mitel Product Security Advisory 20-0013

Mitel MiVoice SIP, MiNet and DECT Phones Information Disclosure (KNOB) Vulnerability

Advisory ID: 20-0013

Publish Date: 2020-11-02

Last Updated: 2020-11-02

Revision: 1.0



Bluetooth enabled Mitel MiVoice 6940, 6930 and 6873i SIP and MiNet phones could allow an attacker to conduct brute-force attacks, which is also known as a “KNOB” attack. If successful, this attack can decrypt and eavesdrop on communications. This is due to Bluetooth industry specifications that allowed low encryption key length and does not prevent an attacker from influencing the key length negotiation between two Bluetooth devices.

This vulnerability was discovered by security researchers and potentially affects all Bluetooth devices. To address this vulnerability, the Bluetooth specifications have been updated by the industry consortium, Bluetooth SIG (Special Interest Group). Mitel has implemented these updated specifications in affected products listed below.

Mitel is recommending customers with affected product versions to update to the latest release.


Affected Products




Risk Assessment

The risk for this vulnerability is rated from Medium to High. Refer to the product Security Bulletins for additional statements regarding risk.


Mitigation / Recommended Action

Mitel has issued new releases of the affected software. Customers are advised to update their software to the latest versions.


To successfully exploit this vulnerability the attacker’s device must be in proximity (within Bluetooth range) of two vulnerable Bluetooth devices. In addition, the attacker must successfully execute a Man-in-the-Middle attack within a narrow time window while both vulnerable devices are initiating Bluetooth pairing.

Customers are advised to review the product Security Bulletin. For additional information, contact Product Support.


External References




Related CVEs / CWEs / Advisories



Revision History

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