CVE-2026-20184

CRITICAL

Cisco Webex Meetings Certificate Validation Vulnerability

Title source: cna
STIX 2.1

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.

Scores

CVSS v3 9.8
EPSS 0.0007
EPSS Percentile 20.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

CWE
CWE-295
Status published
Products (50)
Cisco/Cisco Webex Meetings 39.10
Cisco/Cisco Webex Meetings 39.11
Cisco/Cisco Webex Meetings 39.6
Cisco/Cisco Webex Meetings 39.7
Cisco/Cisco Webex Meetings 39.7.4
Cisco/Cisco Webex Meetings 39.7.7
Cisco/Cisco Webex Meetings 39.8
Cisco/Cisco Webex Meetings 39.8.2
Cisco/Cisco Webex Meetings 39.8.3
Cisco/Cisco Webex Meetings 39.8.4
... and 40 more
Published Apr 15, 2026
Tracked Since Apr 15, 2026