cisco-sa-cucm-ssrf-cXPnHcWCriticalCVSS 8.6

Cisco Unified Communications Manager Server-Side Request Forgery Vulnerability

Published
June 3, 2026
Last Modified
July 1, 2026

🔗 CVE IDs covered (1)

CVE-2026-20230 →

📋 Description

A vulnerability in Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an unauthenticated, remote attacker to conduct server-side request forgery (SSRF) attacks through an affected device.

This vulnerability is due to improper input validation for specific HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to write files to the underlying operating system that could be used later to elevate to root.

Note: Cisco has assigned this security advisory a Security Impact Rating (SIR) of Critical rather than High as the score indicates. The reason is that exploitation of this vulnerability could result in an attacker elevating privileges to root.

Note: To exploit this vulnerability, the WebDialer service must be enabled. WebDialer is disabled by default.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

CVE-2026-20230 — Cisco Unified Communications Manager Server-Side Request Forgery Vulnerability (CVSS 3.1 8.6, CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N)

🎯 Affected products23

  • Cisco Unified Communications Manager
  • Cisco Unified Communications Manager 14
  • Cisco Unified Communications Manager 14SU1
  • Cisco Unified Communications Manager 14SU2
  • Cisco Unified Communications Manager 14SU3
  • Cisco Unified Communications Manager 14SU4
  • Cisco Unified Communications Manager 14SU4a
  • Cisco Unified Communications Manager 14SU5
  • Cisco Unified Communications Manager 15
  • Cisco Unified Communications Manager 15.0.1.13010-1
  • Cisco Unified Communications Manager 15.0.1.13011-1
  • Cisco Unified Communications Manager 15.0.1.13012-1
  • Cisco Unified Communications Manager 15.0.1.13013-1
  • Cisco Unified Communications Manager 15.0.1.13014-1
  • Cisco Unified Communications Manager 15.0.1.13015-1
  • Cisco Unified Communications Manager 15.0.1.13016-1
  • Cisco Unified Communications Manager 15.0.1.13017-1
  • Cisco Unified Communications Manager 15SU1
  • Cisco Unified Communications Manager 15SU1a
  • Cisco Unified Communications Manager 15SU2
  • Cisco Unified Communications Manager 15SU3a
  • Cisco Unified Communications Manager 15SU4
  • Cisco Unified Communications Manager 15SU4a

✅ Remediation

Cisco has released software updates that address this vulnerability. https://software.cisco.com Workarounds: There are no workarounds that address this vulnerability. However, as a mitigation, administrators may disable the WebDialer service until a patch can be applied. To disable WebDialer, complete the following steps: Log in to the Cisco Unified CM Administration interface. From the Navigation menu, choose Cisco Unified Serviceability and click Go. From the Tools menu, choose Service Activation. In the CTI Services section of the page, uncheck the Cisco WebDialer Web Service check box and click Save. While this mitigation has been deployed and was proven successful in a test environment, customers should determine the applicability and effectiveness in their own environment and under their own use conditions. Customers should be aware that any workaround or mitigation that is implemented may negatively impact the functionality or performance of their network based on intrinsic customer deployment scenarios and limitations. Customers should not deploy any workarounds or mitigations before first evaluating the applicability to their own environment and any impact to such environment.

🔗 References (2)