CVE-2026-41671

Admidio: OIDC Token Introspection Endpoint Returns Active for All Tokens Without Validation

Published May 7, 2026 CVSS 3.1 · 6.8 Medium EPSS < 1% KEV · Not listed
Description
Admidio is an open-source user management solution. Prior to version 5.0.9, the OIDC token introspection endpoint (/modules/sso/index.php/oidc/introspect) always returns {"active": true} for every request, regardless of whether a valid token is provided, whether the token is expired, revoked, or completely fabricated. The endpoint performs no authentication of the calling resource server and no validation of the submitted token. Any resource server that relies on this introspection endpoint to validate access tokens will accept all requests as authorized, enabling complete authentication bypass. Additionally, the OIDC token revocation endpoint (/oidc/revoke) returns {"revoked": true} without actually revoking any token, preventing resource servers from invalidating compromised credentials. This issue has been patched in version 5.0.9.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-9xx5-cv6j-x533 Admidio: OIDC Token Introspection Endpoint Returns Active for All Tokens Without Validation
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Admidio
Admidio admidio
Vendors & Products Admidio
Admidio admidio
Type Values Removed Values Added
Description Admidio is an open-source user management solution. Prior to version 5.0.9, the OIDC token introspection endpoint (/modules/sso/index.php/oidc/introspect) always returns {"active": true} for every request, regardless of whether a valid token is provided, whether the token is expired, revoked, or completely fabricated. The endpoint performs no authentication of the calling resource server and no validation of the submitted token. Any resource server that relies on this introspection endpoint to validate access tokens will accept all requests as authorized, enabling complete authentication bypass. Additionally, the OIDC token revocation endpoint (/oidc/revoke) returns {"revoked": true} without actually revoking any token, preventing resource servers from invalidating compromised credentials. This issue has been patched in version 5.0.9.
Title Admidio: OIDC Token Introspection Endpoint Returns Active for All Tokens Without Validation
Weaknesses CWE-287
References
Metrics cvssV3_1

{'score': 6.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 7, 2026, 12:46 PM
Reserved
Apr 22, 2026, 3:53 AM
Status
Deferred
Published
May 7, 2026, 4:16 AM
Modified
Jun 17, 2026, 10:46 AM