CVE-2026-20184CWE-295

Cisco Webex Meetings Certificate Validation Vulnerability

Critical · published April 15, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
43.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00520 · 43.3th percentile
Weakness
CWE-295 · Improper Certificate Validation
Published
2026-04-15T16:03Z
EPSS history
Timeline
  • 15 APR 16:03Z
    Cisco Webex Meetings Certificate Validation Vulnerability
    cvelistv5