9.8
CRITICAL CVSS 3.1
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.

INFO

Published Date :

April 15, 2026, 5:17 p.m.

Last Modified :

April 17, 2026, 3:09 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-20184 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Cisco webex
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL [email protected]
Solution
Apply security updates for Cisco Webex Services to correct improper certificate validation.
  • Update Cisco Webex Services to the latest version.
  • Validate SSO integration certificate configurations.
  • Restart relevant services if required.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-20184.

URL Resource
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-cui-cert-8jSZYhWL
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-20184 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-20184 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-20184 vulnerability anywhere in the article.

  • The Cyber Express
Cisco Patches Critical ISE Vulnerabilities Allowing Remote Code Execution Attacks

Cisco has released security updates to fix multiple vulnerabilities in its Identity Services Engine and Webex Services, warning that successful exploitation could lead to remote code execution, root-l ... Read more

Published Date: Apr 20, 2026 (2 weeks, 2 days ago)
  • The Hacker News
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 an ... Read more

Published Date: Apr 16, 2026 (2 weeks, 6 days ago)
  • CybersecurityNews
Cisco Webex Services Vulnerability Let Remote Attacker Impersonate Any User

Cisco has issued a critical security advisory warning of a severe vulnerability in its cloud-based Webex Services. Tracked as CVE-2026-20184, this flaw carries a maximum Common Vulnerability Scoring S ... Read more

Published Date: Apr 16, 2026 (2 weeks, 6 days ago)
  • Daily CyberSecurity
RedSun: New Windows Defender Zero-Day Turns Protector into Attacker, PoC Publishes

Just as the cybersecurity community began digesting the latest round of patches for the high-profile “BlueHammer” vulnerability, a new storm has appeared on the horizon. On April 16, 2026, the securit ... Read more

Published Date: Apr 16, 2026 (2 weeks, 6 days ago)
  • Daily CyberSecurity
Critical 9.8 Webex Flaw Lets Attackers Impersonate Any User

In the modern enterprise, the Single Sign-On (SSO) portal is the master key to a company’s digital life. However, a recently disclosed critical vulnerability in Cisco Webex Services has revealed how a ... Read more

Published Date: Apr 16, 2026 (2 weeks, 6 days ago)

The following table lists the changes that have been made to the CVE-2026-20184 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 15, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-295
    Added Reference https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-cui-cert-8jSZYhWL
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.