CVE-2011-2561: Cisco Unified Communications Manager

High severity, CVSS 7.1. EPSS: 1.1% chance of exploitation in the next 30 days.

The SIP process in Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 7.x before 7.1(5b)su4 and 8.x before 8.0(1) does not properly handle SDP data within a SIP call in certain situations related to use of the g729ar8 codec for a Media Termination Point (MTP), which allows remote attackers to cause a denial of service (service outage) via a crafted call, aka Bug ID CSCtc61990.

Affected products

• Cisco Unified Communications Manager: version 7.0(1)su1 only; version 7.0(1)su1a only; version 7.0(2) only; version 7.0(2a) only; version 7.0(2a)su1 only; version 7.0(2a)su2 only; …

Published 2011-08-29. Last modified 2026-06-16.