CVE Catalog

CVE-2026-86466

Low risk· EPSS 4%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.14%

4th percentile - higher than 4% of all known CVEs

Summary

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.

Risk Assessment

An attacker with a valid token for any other application served by the same Authentik instance may gain unauthorized access to Airflow as another user. The risk affects deployments using Authentik OAuth with the FAB auth manager.

Recommendation

Upgrade apache-airflow-providers-fab to version 3.9.0 or later, which fixes the issue. Deployments that applied the CVE-2026-75156 fix and use Authentik must also upgrade to this version.

Other vulnerabilities in Apache Airflow FAB provider

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Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS