CVE-2026-20184

CRITICAL

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.

CVSS v3.1 Score

9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Published: 4/15/2026Modified: 4/17/2026

Related Intelligence (4)

CRITICALVulnerability

Cisco Systems issues three advisories for critical vulnerabilities in Webex, ISE

Admins who use Cisco Webex Services configured to use trust anchors within the SSO integration with Control Hub must install a new identity provider certificate to close a critical vulnerability, or risk losing access control. Cisco said in an advisory this week that admins must upload a new identity provider (IdP) SAML certificate to Webex Control Hub, the web-based management portal where IT adm

CVE-2026-20184CVE-2026-20147
CSO Online
CRITICALVulnerability

Cisco Webex SSO flaw needs manual certificate update to fix

Admins who use Cisco Webex Services configured to use trust anchors within the SSO integration with Control Hub must install a new identity provider certificate to close a critical vulnerability, or risk losing access control. Cisco said in an advisory this week that admins must upload a new identity provider (IdP) SAML certificate to Webex Control Hub, the web-based management portal where IT adm

CVE-2026-20184CVE-2026-20147
CSO Online
CRITICALVulnerability

Cisco Patches Four Critical Identity Services, Webex Flaws Enabling Code Execution

Cisco has announced patches to address four critical security flaws impacting Identity Services and Webex Services that could result in arbitrary code execution and allow an attacker to impersonate any user within the service. The details of the vulnerabilities are below - CVE-2026-20184 (CVSS score: 9.8) - An improper certificate validation in the integration of single sign-on (SSO)

CVE-2026-20184
The Hacker News
CRITICALVulnerability

NVD CRITICAL: CVE-2026-20184 — A vulnerability in the integration of single sign-on (SSO) with Control Hub in C...

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 end

CVE-2026-20184
NIST NVD

References (1)

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-cui-cert-8jSZYhWL