CVE-2026-59242
Apache Airflow: Arbitrary airflow.* class instantiation on the API server via the XCom deserialize endpoint
MEDIUM 5.4
At a glance
- Source
- NVD
- EPSS
- EPSS 0.53 % · percentile 45 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- apache
- NVD status
- Analyzed
Description
Apache Airflow's XCom `GET /api/v2/{...}/xcomEntries/{key}?deserialize=true` endpoint passed a string-literal payload through `BaseXCom.deserialize_value` without the `_check_forbidden_xcom_keys` guard, allowing an authenticated API user with XCom write-and-read access to instantiate arbitrary `airflow.*` classes on the API server (CWE-502). An authenticated user who can write an XCom value and then read it back with `deserialize=true` triggers the unsafe instantiation. Users are advised to upgrade to apache-airflow 3.3.1 or later, which rejects reserved XCom serialization keys submitted as JSON string literals.
Weaknesses (CWE)
- CWE-502 — Deserialization of Untrusted Data
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N | CISA-ADP |
| CVSS 3.1 | MEDIUM 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N | NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary) |
Advisories
- GHSA-fcmm-42r9-mmmm — Apache Airflow XCom API permits unsafe deserialization through JSON string literals
- PYSEC-2026-3992 — Apache Airflow's XCom `GET /api/v2/{...}/xcomEntries/{key}?deserialize=true` endpoint passed a string-literal payload through `BaseXCom.deserialize_value` witho
European references
- ENISA EUVD · EUVD-2026-57312
- GCVE · GCVE-0-2026-59242
Affected configurations (NVD CPE)
cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:*< 3.3.1
Affected products
| Product | Versions |
|---|---|
| Apache Software Foundation · Apache Airflow | affected 0 < 3.3.1 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |