The Bluetooth handset of Mitel MiVoice 6873i, 6930, and 6940 SIP phones with firmware before 5.1.0.SP6 could allow an unauthenticated attacker within Bluetooth range to pair a rogue Bluetooth device when a phone handset loses connection, due to an improper pairing mechanism. A successful exploit could allow an attacker to eavesdrop on conversations.

Mitel 6800 and 6900 Series SIP phone devices through 2022-04-27 have "undocumented functionality." A vulnerability in Mitel 6800 Series and 6900 Series SIP phones excluding 6970, versions 5.1 SP8 (5.1.0.8016) and earlier, and 6.0 (6.0.0.368) through 6.1 HF4 (6.1.0.165), could allow a unauthenticated attacker with physical access to the phone to gain root access due to insufficient access control for test functionality during system startup. A successful exploit could allow access to sensitive information and code execution.

A key length vulnerability in the implementation of the SRTP 128-bit key on Mitel 6800 and 6900 SIP series phones, versions 5.1.0.2051 SP2 and earlier, could allow an attacker to launch a man-in-the-middle attack when SRTP is used in a call. A successful exploit may allow the attacker to intercept sensitive information.