Apache Airflow: Authorization bypass in the Backfill API through conflicting interpretations of the backfill id
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and GitHub.
Summary
Apache Airflow's Backfill API authorized a request against a Dag id supplied by the caller whenever the `backfill_id` path segment failed to parse. The authorization dependency parsed it with `int()` while the route handler parsed it as pydantic's `NonNegativeInt`, which accepts values `int()` rejects (`1.0` coerces to `1`); FastAPI resolves dependencies before endpoint validation, so the two acted on different Dags. An authenticated user holding edit permission on any single Dag could therefore read, pause and cancel backfills belonging to any other Dag, including moving another Dag's queued runs to `failed`. No non-default configuration is required and backfill ids are sequential, so finding a target is trivial. Users are advised to upgrade to apache-airflow 3.3.1 or later, which parses the backfill id with the same type the routes declare.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Apache Airflow (Apache Software Foundation) Fixed in 3.0.0
- Fix · CNA Apache Airflow (Apache Software Foundation) Fixed in 3.3.1
- Fix · GHSA-j4jc-cq9h-xrhr apache-airflow (PyPI) Fixed in 3.3.1 Advisory →
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
Apache Airflow 3.3.1
12 records Highest priority Priority MEDIUM 2 MEDIUM, 10 LOW
Other records, highest priority first
- TI-2026-47748 Apache Airflow: DAG-author remote code execution on the Scheduler via a Serde `Callback` deserialization gadgetPriority MEDIUM 41
- TI-2026-41827 Deserialization of untrusted data in Apache AirflowPriority MEDIUM 41
- TI-2026-47565 Apache Airflow: DAG-author remote code execution on the Scheduler via awaiting_input next_kwargs deserializationPriority LOW 39
- Release ·
Apache Airflow 3.0.0
8 records Highest priority Priority LOW 8 LOW
Other records, highest priority first
- TI-2026-48482 Apache Airflow: Cross-team authorization bypass in the asset materialization and dag-run result endpointsPriority LOW 29
- TI-2026-48480 Apache Airflow: Bulk Variable and Connection endpoints record secret values in the audit log in cleartextPriority LOW 29
- TI-2026-48481 Apache Airflow: Values of a list-shaped Variable are not masked in task logs and the Rendered Templates UIPriority LOW 28
Timeline
- 2026-10-02 Threatist record created from CVE-2026-68968
- 2026-10-03 Alias added: GHSA-j4jc-cq9h-xrhr
- 2026-10-07 EPSS moved to the below the 50th percentile
- 2026-11-03 Fix available: [email protected], [email protected] · CNA
References
Advisory 2
Other 6
- https://github.com/apache/airflow/commit/6fcae4e2b0aabd22b006659bc47139a124813865
- https://github.com/apache/airflow/commit/bbb97f55e647dd09f0725c111b7a7081b9df7850
- https://github.com/apache/airflow
- https://github.com/apache/airflow/releases/tag/3.3.1
- https://github.com/pypa/advisory-database/tree/main/vulns/apache-airflow/PYSEC-2026-3710.yaml
- http://www.openwall.com/lists/oss-security/2026/08/12/12
More Apache Airflow vulnerabilities
- TI-2020-10905 Missing authentication in Apache Airflow KEVCVSS 3.1CRITICAL 9.8
- TI-2020-09638 OS command injection in Apache Airflow KEVCVSS 3.1HIGH 8.8
- TI-2022-19017 Apache Airflow <2.4.0 has an RCE in a bash example CVSS 3.1HIGH 8.8
- TI-2021-16140 Apache Airflow: Variable Import endpoint missed authentication check CVSS 3.1CRITICAL 9.8
- TI-2022-08169 Apache Airflow: RCE in example DAGs CVSS 3.1HIGH 8.8
- TI-2024-26776 Apache Airflow: DAG Author Code Execution possibility in airflow-scheduler CVSS 3.1HIGH 8.8
Sources
- CVE-2026-68968 · CVE Program
- CVE-2026-68968 · NVD
- FIRST EPSS
- GHSA-j4jc-cq9h-xrhr · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences