CVE-2026-42359
CVE-2026-42359 · Apache Airflow: Authenticated RCE via XCom PATCH endpoint — XComUpdateBody missing FORBIDDEN_XCOM_KEYS validator
This page contains facts from public vulnerability sources. Check the original advisory before updating.
A bug in Apache Airflow's XCom PATCH endpoint `PATCH /api/v2/xcomEntries/{key}` allowed an authenticated UI/API user with XCom write permission on a Dag to set XCom entries under reserved key names (e.g. `return_value`) that the matching POST endpoint already validated against `FORBIDDEN_XCOM_KEYS`. The endpoint also accepted serialized payload shapes the triggerer's deserializer treats as code; combined, this allowed RCE on the triggerer when the affected task next deferred. Affects deployments where untrusted users have XCom write permission on Dags that defer to the triggerer. This is a fix-bypass of CVE-2026-33858: PR #64148 added the `FORBIDDEN_XCOM_KEYS` validator only on the POST/set path; the PATCH path was not covered. Users who already upgraded for CVE-2026-33858 should additionally upgrade to `apache-airflow` 3.2.2 or later to cover the PATCH-path bypass.
CVSS 8.8 · High · EPSS 0.6% · Fix available
- Published
- Updated
Stack: python
Affected products and versions
apache airflow
- Versions
- ≥ 3.2.0, < 3.2.2: Affected (semver)
Update to 3.2.2
apache-airflow PyPI
- Versions
- 3.2.0
- 3.2.1
- 3.2.1rc1
- 3.2.1rc2
- 3.2.1rc3
- 3.2.2rc1
- 3.2.2rc2
- 3.2.2rc3
- Affected ranges
- ECOSYSTEM: ≥ 3.2.0, < 3.2.2
Update to 3.2.2