Vulnerability Note VU#430969

Cisco Firewall Services Module vulnerable to DoS via inspection of malformed SIP messages

Original Release date: 16 Feb 2007 | Last revised: 22 Feb 2007


Cisco Firewall Services Module fails to properly inspect SIP messages. This vulnerability may allow a remote attacker to cause a denial of service condition.


The Cisco Firewall Services Module is an integrated firewall service for Cisco Catalyst 6500 series switches and Cisco 7600 series routers. This module fails to properly inspect SIP messages which may cause the system to crash. This vulnerability can be exploited when an attacker sends a specially crafted SIP message to the system.

Cisco states that SIP inspection is enabled by default in 2.x versions of the module.


A remote, unauthenticated attacker may be able to cause the system to crash.



Cisco states this issue has been addressed in 2.3(4.12) for the 2.3.x series, and 3.1(3.24) for the 3.x series. Please see Cisco Security Advisory cisco-sa-20070214-fwsm for further information.


Disable deep packet inspection. Please see Cisco Security Advisory cisco-sa-20070214-fwsm for further information.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Cisco Systems, Inc.Affected-16 Feb 2007
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



Thanks to Cisco Systems Product Security Incident Response Team for reporting this vulnerability.

This document was written by Katie Steiner.

Other Information

  • CVE IDs: CVE-2007-0961
  • Date Public: 14 Feb 2007
  • Date First Published: 16 Feb 2007
  • Date Last Updated: 22 Feb 2007
  • Severity Metric: 12.60
  • Document Revision: 9


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