VTU/CODEC is not properly configured to support streaming.

In the event conference streaming directly from a VTU/CODEC is approved for a given conference, the administrator will need to properly configure the VTU to support the streamed conference. One of these measures is to set a one-time-use password for the streamed media. Another measure is to install configuration settings to limit the reach of the streamed media across the network to only those portions that are to receive it. This is done by setting the TTL as low as possible. A mitigation that can be used for the lack of access control for IP multicast is to use different multicast addresses and IP ports each time a streaming session is configured. First these should never be the default address(es) or ports used by the vendor’s system and they should be randomly selected.

Note: Streaming is a feature of the VTU that could be turned on and configured for monitoring purposes by an adversary if the administrative access to the VTU is compromised. This is another reason why it is imperative to change all access codes and passwords on the VTU as required earlier. Additionally, users must be trained to recognize any displayed indication provided by the VTU that it is in streaming mode.

Note: For additional information regarding the vulnerabilities associated with VTC streaming, see the discussion under RTS-VTC 2340