CVE-2026-59242: Apache Airflow

Medium severity, CVSS 5.4. EPSS: 0.5% chance of exploitation in the next 30 days.

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.

Affected products

• Apache Airflow: before 3.3.1 (fixed in 3.3.1)

Published 2026-08-12. Last modified 2026-09-16.