CVE-2026-20184
Cisco Webex Meetings Certificate Validation Vulnerability
Description
A vulnerability in the integration of single sign-on (SSO) with Control Hub in Cisco Webex Services could have allowed an unauthenticated, remote attacker to impersonate any user within the service. This vulnerability existed because of improper certificate validation. Prior to this vulnerability being addressed, an attacker could have exploited this vulnerability by connecting to a service endpoint and supplying a crafted token. A successful exploit could have allowed the attacker to gain unauthorized access to legitimate Cisco Webex services.
Weakness: CWE-295
Affected products
| Vendor | Product | Category | Matched by |
|---|---|---|---|
| Cisco | Cisco Webex | Other Products | cna-assigner |
Vendor-reported products (1)
- Cisco · Cisco Webex Meetings
Vendor advisory
cisco-sa-webex-cui-cert-8jSZYhWL
Cisco Webex Services Certificate Validation Vulnerability
Cisco’s rating: Critical (advisory CVSS 9.8) · Published Apr 15, 2026 · updated Apr 16, 2026 (revision 1.1)
Bug ID: CSCwt37111
The vendor’s rating applies to the whole advisory and can differ from this CVE’s own CVSS severity. Where this comes from