CVEvulnerability

CVE-2026-42359

8.8 HIGH Published 2026-06-01 Modified 2026-07-21 Official page ↗
Status
Analyzed
Published
2026-06-01
Last modified
2026-07-21
Assigner
[email protected]
CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
8.8 HIGH — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weaknesses
CWE-502

Description

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 configurations

• apache airflow (>= 3.2.0 < 3.2.2)

Related

Weakness · CWE (1)

  • CWE-502 Deserialization of Untrusted Data weakness

References