CVE-2026-20230
Cisco Unified Communications Manager Server-Side Request Forgery Vulnerability
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.
Weakness: CWE-918
Affected products
| Vendor | Product | Category | Matched by |
|---|---|---|---|
| Cisco | Cisco Unified Communications Manager | Other Products | cna-assigner |
Vendor-reported products (1)
- Cisco · Cisco Unified Communications Manager
Vendor advisory
Cisco Unified Communications Manager Server-Side Request Forgery Vulnerability
Cisco’s rating: Critical (advisory CVSS 8.6) · Published Jun 3, 2026 · updated Jul 1, 2026 (revision 1.1)
Bug ID: CSCws67331
The vendor’s rating applies to the whole advisory and can differ from this CVE’s own CVSS severity. Where this comes from