How severe is CVE-2011-2561?

CVE-2011-2561 has a CVSS 2.0 base score of 7.1, rated high severity.

Is CVE-2011-2561 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-2561?

CVE-2011-2561 primarily affects Cisco Unified Communications Manager. In total, 27 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-2561?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2011-2561 published?

CVE-2011-2561 was published on 2011-08-29 and last updated on 2026-06-16.

CVE-2011-2561

CVE-2011-2561 is a high-severity vulnerability in Cisco Unified Communications Manager with a CVSS 2.0 base score of 7.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-399.

Key facts

Severity: High (CVSS 2.0 base score 7.1)
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-399
Affected product: Cisco Unified Communications Manager
Published: 2011-08-29
Last modified: 2026-06-16

Description

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.

Frequently asked questions

What is CVE-2011-2561?: 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.
How severe is CVE-2011-2561?: CVE-2011-2561 has a CVSS 2.0 base score of 7.1, rated high severity.
Is CVE-2011-2561 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-2561?: CVE-2011-2561 primarily affects Cisco Unified Communications Manager. In total, 27 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-2561?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2011-2561 published?: CVE-2011-2561 was published on 2011-08-29 and last updated on 2026-06-16.

References

http://www.cisco.com/en/US/products/products_security_advisory09186a0080b8f531.shtml

Affected products (27)

cpe:2.3:a:cisco:unified_communications_manager:7.0\(1\)su1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.0\(1\)su1a:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.0\(2\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.0\(2a\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.0\(2a\)su1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.0\(2a\)su2:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(2a\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(2a\)su1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(2b\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(2b\)su1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(3\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(3a\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(3a\)su1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(3a\)su1a:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(3b\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(3b\)su1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(3b\)su2:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5\)su1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5\)su1a:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5a\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5b\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5b\)su1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5b\)su1a:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5b\)su2:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:7.1\(5b\)su3:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:8.0:*:*:*:*:*:*:*

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