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
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.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | apache-airflow | >= 3.2.0, < 3.2.2 | 3.2.2 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-42359
- https://github.com/apache/airflow/pull/65915
- https://github.com/apache/airflow
- https://github.com/pypa/advisory-database/tree/main/vulns/apache-airflow/PYSEC-2026-185.yaml
- https://lists.apache.org/thread/g8dqykpf1p90tysq8tln4qtkqwb1038s
- https://www.cve.org/CVERecord?id=CVE-2026-33858
- https://github.com/advisories/GHSA-wr76-29cr-67w8
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H- Weakness (CWE)
CWE-502- Platform
- Python (PyPI)
- Package
apache-airflow- Disclosed
- 01.06.2026
- Updated
- 11.10.2026 14:18
Sources and licenses
OSV / GitHub Advisory Database - GHSA-wr76-29cr-67w8 - CC BY 4.0
OSV / GitHub Advisory Database - PYSEC-2026-185 - PyPA Advisory Database; CC BY 4.0
Vulnerability history: apache-airflow
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 158
- First → latest
- 08.2018 09.2026
- Without a fix
- 4
- Exploited in attacks
- 2
Severity breakdown
- Critical 16
- High 49
- Medium 86
- Low 7
Disclosures per year
- 2018: 1
- 2019: 8
- 2020: 12
- 2021: 5
- 2022: 16
- 2023: 31
- 2024: 18
- 2025: 6
- 2026: 61
-
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 this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.