Severity: moderate Affected versions:
- Apache Airflow FAB provider (apache-airflow-providers-fab) before 3.7.3 Description: The FAB auth manager's Azure AD OAuth login defaulted `verify_signature=False` when decoding the ID token, so an attacker able to present a forged or unsigned (`alg:none`) ID token to the OAuth callback could bypass authentication and log in as an arbitrary user, including one holding the Admin role (CWE-347). Deployments running the FAB auth manager with the Azure AD OAuth login path under its default configuration are affected; the Authentik path already defaulted to `True`. This issue affects `apache-airflow-providers-fab` before 3.7.3. Users are advised to upgrade to `apache-airflow-providers-fab` 3.7.3, which defaults `verify_signature=True`. Credit: MalHyuk (finder) Jarek Potiuk (remediation developer) References: https://github.com/apache/airflow/pull/69374 https://airflow.apache.org/ https://www.cve.org/CVERecord?id=CVE-2026-59243
