CVE-2026-20184

CVE Enrichment

CVSS: 9.8 CRITICAL
EPSS: 0.52%
EPSS Percentile: 44.31%
CISA KEV: Not listed

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.

Technical Details

CVSS Version: 3.1
CNA / NVD Source: [email protected]
Published: 16-Apr-2026 00:17
Last Modified: 27-Oct-2026 05:10
EPSS Date: 2026-11-05
CWE: CWE-295

CVSS Vector


            CVSS:3.1                            AV:N /
                            AC:L /
                            PR:N /
                            UI:N /
                            S:U /
                            C:H /
                            I:H /
                            A:H

CNA Products / Version Status

Cisco · Cisco Webex Meetings Source: CNA · [email protected]
Default status: unknown

39.7.7 — affected
39.9 — affected
40.4.10 — affected
39.6 — affected
40.6.2 — affected
39.8.2 — affected
39.8.4 — affected
40.1 — affected
39.11 — affected
39.7.4 — affected
39.9.1 — affected
40.4 — affected
40.6 — affected
39.7 — affected
39.8 — affected
39.8.3 — affected
40.2 — affected
39.10 — affected
42.6 — affected
42.7 — affected
42.8 — affected
42.9 — affected
42.10 — affected
42.11 — affected
42.12 — affected
43.1 — affected
43.2 — affected
43.3 — affected
43.4 — affected
43.4.1 — affected
43.4.2 — affected
43.5.0 — affected
43.6.0 — affected
43.6.1 — affected
43.7 — affected
43.8 — affected
43.9 — affected
43.10 — affected
43.11 — affected
43.12 — affected
44.1 — affected
44.2 — affected
44.3 — affected
44.4 — affected
44.5 — affected
44.6 — affected
44.7 — affected
44.8 — affected
44.9 — affected
44.10 — affected
44.11 — affected
44.12 — affected
45.1 — affected
45.2 — affected
45.3 — affected
45.4 — affected

References

[email protected]

Last enrichment sync: 05-Nov-2026 22:46
Sources: NVD · FIRST EPSS · CISA KEV
Latest successful provider update; providers refresh independently.

Reported Context (2)

The Webex Services bug (CVE-2026-20184) in SSO certificate validation could allow unauthenticated attackers to impersonate any user. Cisco Patches ISE and Webex Flaws That Could Enable RCE and User Impersonation
Cisco released security updates addressing four critical vulnerabilities, including a Webex SSO certificate-validation flaw (CVE-2026-20184) that could let unauthenticated attackers impersonate users. Cisco patches critical Webex SSO flaw and requires customers to upload a new SAML certificate

CVE (4)

Malware (1)

People (1)

MITRE ATT&CK (1)

Vendors (1)

Products (6)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.