CVE-2026-86466

Apache Airflow FAB provider: FAB Authentik provider: id_token issuer/audience not validated

Published Sep 16, 2026 CVSS 3.1 · 8.1 High EPSS < 1% KEV · Not listed
Description
Apache Airflow FAB provider: the Authentik OAuth path in the FAB auth manager does not validate the issuer or audience claims of the id_token it accepts. An attacker holding a token that the same Authentik identity provider minted for a different client application can present it to Airflow and be authenticated as the user it names, because the audience claim is never checked. Affects deployments using the FAB auth manager with Authentik OAuth where the same Authentik instance also serves other applications; the attacker needs a valid token for any of those other applications, not for Airflow.

CVE-2026-75156 corrected the same missing validation on the Azure AD path in this file; the Authentik path was left unchanged and is fixed here. Deployments that applied the CVE-2026-75156 fix and use Authentik must also upgrade for this one.

Users of apache-airflow-providers-fab are recommended to upgrade to version 3.9.0 or later, which fixes the issue.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Apache apache-airflow-providers-fab
CPEs cpe:2.3:a:apache:apache-airflow-providers-fab:*:*:*:*:*:*:*:*
Vendors & Products Apache apache-airflow-providers-fab
Type Values Removed Values Added
First Time appeared Apache
Apache airflow Fab Provider
Vendors & Products Apache
Apache airflow Fab Provider
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Apache Airflow FAB provider: the Authentik OAuth path in the FAB auth manager does not validate the issuer or audience claims of the id_token it accepts. An attacker holding a token that the same Authentik identity provider minted for a different client application can present it to Airflow and be authenticated as the user it names, because the audience claim is never checked. Affects deployments using the FAB auth manager with Authentik OAuth where the same Authentik instance also serves other applications; the attacker needs a valid token for any of those other applications, not for Airflow. CVE-2026-75156 corrected the same missing validation on the Azure AD path in this file; the Authentik path was left unchanged and is fixed here. Deployments that applied the CVE-2026-75156 fix and use Authentik must also upgrade for this one. Users of apache-airflow-providers-fab are recommended to upgrade to version 3.9.0 or later, which fixes the issue.
Title Apache Airflow FAB provider: FAB Authentik provider: id_token issuer/audience not validated
Weaknesses CWE-346
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
apache
Published
Updated
Sep 17, 2026, 7:21 PM
Reserved
Sep 7, 2026, 2:27 PM
Status
Analyzed
Published
Sep 16, 2026, 10:16 AM
Modified
Sep 18, 2026, 2:29 PM