CVE-2023-20116

CVE-2023-20116 is a medium-severity vulnerability in Cisco Unified Communications Manager with a CVSS 3.x base score of 6.8. 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-835.

Key facts

• Severity: Medium (CVSS 3.x base score 6.8)
• EPSS exploit prediction: 1% (45th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-835
• Affected product: Cisco Unified Communications Manager
• Published: 2023-06-28
• Last modified: 2026-06-17

Description

A vulnerability in the Administrative XML Web Service (AXL) API of Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of user-supplied input to the web UI of the Self Care Portal. An attacker could exploit this vulnerability by sending crafted HTTP input to an affected device. A successful exploit could allow the attacker to cause a DoS condition on the affected device.

Frequently asked questions

What is CVE-2023-20116?

A vulnerability in the Administrative XML Web Service (AXL) API of Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of user-supplied input to the web UI of the Self Care Portal. An attacker could exploit this vulnerability by sending crafted HTTP input to an affected device. A successful exploit could allow the attacker to cause a DoS condition on the affected device.

How severe is CVE-2023-20116?

CVE-2023-20116 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-20116 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-20116?

CVE-2023-20116 primarily affects Cisco Unified Communications Manager. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-20116?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-20116 published?

CVE-2023-20116 was published on 2023-06-28 and last updated on 2026-06-17.

References

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-dos-4Ag3yWbD

Affected products (8)

• cpe:2.3:a:cisco:unified_communications_manager:11.5\(1.10000.6\):*:*:*:*:*:*:*
• cpe:2.3:a:cisco:unified_communications_manager:11.5\(1.10000.6\):*:*:*:session_management:*:*:*
• cpe:2.3:a:cisco:unified_communications_manager:12.0\(1.10000.10\):*:*:*:*:*:*:*
• cpe:2.3:a:cisco:unified_communications_manager:12.0\(1.10000.10\):*:*:*:session_management:*:*:*
• cpe:2.3:a:cisco:unified_communications_manager:12.5\(1.10000.22\):*:*:*:*:*:*:*
• cpe:2.3:a:cisco:unified_communications_manager:12.5\(1.10000.22\):*:*:*:session_management:*:*:*
• cpe:2.3:a:cisco:unified_communications_manager:14.0\(1.10000.20\):*:*:*:*:*:*:*
• cpe:2.3:a:cisco:unified_communications_manager:14.0\(1.10000.20\):*:*:*:session_management:*:*:*

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