Vulnerability Team

The H.323 implementation in Cisco IOS^® Software contains two vulnerabilities that may be exploited remotely to cause a denial of service (DoS) condition on a device that is running a vulnerable version of Cisco IOS Software.
Cisco has released free software updates that address these vulnerabilities. There are no workarounds to mitigate these vulnerabilities other than disabling H.323 on the vulnerable device.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20100922-h323.shtml.

Note:  The September 22, 2010, Cisco IOS Software Security Advisory bundled publication includes six Cisco Security Advisories. Five of the advisories address vulnerabilities in Cisco IOS Software, and one advisory addresses vulnerabilities in Cisco Unified Communications Manager. Each advisory lists the releases that correct the vulnerability or vulnerabilities detailed in the advisory. The table at the following URL lists releases that correct all Cisco IOS Software vulnerabilities that have been published on September 22, 2010, or earlier:
http://www.cisco.com/warp/public/707/cisco-sa-20100922-bundle.shtml

Individual publication links are in "Cisco Event Response: Semiannual Cisco IOS Software Security Advisory Bundled Publication" at the following link:
http://www.cisco.com/web/about/security/intelligence/Cisco_ERP_sep10.html

The Vulnerability Team adviced to users and administrators to review and apply the updates notifications
necessary to help mitigate the risks.

source: securityfocus.com