A security vulnerability has recently been discovered in the UCM series IP PBX firmware version or older. We highly recommend that any UCM customer upgrade their firmware version to or as soon as possible in order to install a permanent fix to this issue. 

The security vulnerability affects the UCM6100 series, UCM6200 series and UCM6510. For more information on the details behind the security issue please read the special security bulletin below. 

Grandstream Security Bulletin GS17-003