Apache Airflow has an authorization bypass in DagRun wait endpoint
Medium6.5CVE-2026-34538 · Published Apr 9, 2026 · updated Sep 10, 2026
Apache Airflow versions 3.0.0 through 3.1.8 DagRun wait endpoint returns XCom result values even to users who only have DAG Run read permissions, such as the Viewer role.This behavior conflicts with the FAB RBAC model, which treats XCom as a separate protected resource, and with the security model documentation that defines the Viewer role as read-only. Airflow uses the FAB Auth Manager to manage access control on a per-resource basis. The Viewer role is intended to be read-only by default, and the security model documentation defines Viewer users as those who can inspect DAGs without accessing sensitive execution results. Users are recommended to upgrade to Apache Airflow 3.2.0 which resolves this issue.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| apache-airflow PyPI | >= 3.0.0, < 3.2.0 | 3.2.0 |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- Severity from
- GitHub (reviewed advisory)
- Weakness
- CWE-668
- Also known as
- BIT-airflow-2026-34538, CVE-2026-34538, PYSEC-2026-21
- nvd.nist.gov/vuln/detail/CVE-2026-34538
- github.com/apache/airflow/pull/64415
- github.com/apache/airflow
- github.com/apache/airflow/releases/tag/3.2.0
- github.com/pypa/advisory-database/tree/main/vulns/apache-airflow/PYSEC-2026-21.yaml
- lists.apache.org/thread/9mq3msqhmgjwdzbr6bgthj4brb3oz9fl
- www.openwall.com/lists/oss-security/2026/04/09/9
More Apache Airflow advisories
All Apache Airflow| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Apr 16 | Apache Airflow: JWT token appearing in logs | Medium7.5 | 3.2.0 |
| Apr 16 | Apache Airflow: RCE by race condition in example_xcom dag | High8.1 | 3.2.0 |
| Apr 15 | Apache Airflow: information disclosure | Medium6.5 | 3.1.8 |
| Apr 13 | Apache Airflow: Unsafe Deserialization via Legacy Serialization Keys (__type/__var) Bypass in XCom API | High8.8 | 3.2.0 |
| Apr 13 | Apache Airflow: Secrets from Airflow config file logged in plain text in DAG run logs UI | Medium | 3.2.0 |
| Apr 9 | Apache Airflow: JWT token still valid after logout | Critical9.1 | 3.2.0 |