V-259936

Discussion

Action cannot be taken to thwart an attempted DOS or compromise if the system administrators responsible for the operation of the SBC and/or the network defense operators are not alerted to the occurrence in real time.

Check Content

Verify the DISN NIPRNet IPVS SBC is configured to notify system administrators and the ISSO when the following conditions occur:
- Any number of malformed SIP, AS-SIP, or SRTP/SRTCP messages are received that could indicate an attempt to compromise the SBC.
- Excessive numbers of SIP or AS-SIP messages are received from any given IP address that could indicate an attempt to cause a DoS.
- Excessive numbers of messages are dropped due to authentication or integrity check failures, potentially indicating an attempt to cause a DoS or effect a man-in-the-middle attack. 

If the SBC does not notify system administrators and the ISSO when attempts to cause a DoS or other suspicious events are detected, this is a finding.

NOTE: The VVoIP system may allow SIP and SRTP traffic encrypted and encapsulated on port 443 from cloud service providers.