OS command injection via DHCP option 66 in Zenitel EdgeAudioClient TFTP provisioning

OS command injection in the TFTP provisioning module of Zenitel EdgeAudioClient before 9.6.3.0, and 10.x before 10.1.3.0, on VSFF6, VSFF8, VSFF8MP, VSFF8MN, and VSFT devices allows unauthenticated adjacent attackers to execute arbitrary commands as root via a crafted DHCP option 66 (TFTP Server Name) value supplied by a rogue DHCP server on the same network segment. The DHCP-supplied value is passed to a shell without sanitization. Devices using DHCP, the default configuration, are affected on every boot and lease renewal.

The same injection is also reachable via the config_update_tftp_server and sw_update_tftp_server configuration fields by an attacker able to modify the device configuration.