A vulnerability in the Mitel 6800 Series, 6900 Series, and 6900w Series SIP Phones, including the 6970 Conference Unit, through R6.4.0.HF1 (R6.4.0.136) could allow an authenticated attacker with administrative privilege to conduct an argument injection attack, due to insufficient parameter sanitization during the boot process. A successful exploit could allow an attacker to execute arbitrary commands within the context of the system.

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.

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.