CVE-2026-20184
Cisco Webex Meetings Certificate Validation Vulnerability
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
9.8
Cisco Webex Meetings Certificate Validation Vulnerability
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.
- Record
CVE-2026-20184- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-295
- Updated
- 2026-11-02
EUVDEUVD-2026-22971
9.8
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.
- Record
EUVD-2026-22971- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-hh5g-g7m5-5vxv
9.8
A vulnerability in the integration of single sign-on (SSO) with Control Hub in Cisco Webex...
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.
- Record
GHSA-hh5g-g7m5-5vxv- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-295
- Updated
- 2026-11-02
NVD
9.8
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.
- Record
CVE-2026-20184- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-295
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-20184 is a critical vulnerability (CVSS 9.8) in Cisco Webex Meetings, published April 15, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.52%, the 44th percentile. No source names a fixed version.