Description
The Nortel Communications Server 1000 provides a means for the systems within a deployment to exchange information and issue commands. Due to a flaw in the command exchange mechanism it is possible to inject arbitrary commands to retrieve information, obtain unauthorized access or cause a Denial of Service (DoS). A total of sixteen independent vulnerabilities have been identified and VoIPshield is awaiting vendor patches prior to publishing them separately with additional detail.
Recommendations
To completely address the issue requires a patch from Nortel. In the short term it is recommended that a VoIP aware IPS product, such as VoIPguard, with signatures to detect attempts to exploit this issue, be implemented to prevent it from being exploited. In addition, implementation of general best practice guidance such as controlling access to telephony networks via VLANs, access control lists, firewalls, network admission controls and/or other security devices will aid in limiting the exposure of this vulnerability. Nortel customers with a valid support agreement may wish to speak with their support contact in order to obtain additional vendor details.