Cisco Unified Communications Manager Improper Access Control Vulnerability

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 access control bypass attacks on 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 access parts of the network that are beyond the scope of their intended access.

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

This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of October 21, 2026, Security Advisories ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-notice-QGwHnJ6k"]. In addition, for further documentation of improvements and fixes in Cisco Unified CM, see Cisco Unified Communications Products Security Hardening Release: October 2026 ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voice-hardening-twgbH9e3"].

CVE-2026-76487 — Cisco Unified Communications Manager Improper Access Control Vulnerability (CVSS 3.1 5.3, CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)