{"schema_version": "1.6.1", "id": "CVE-2026-59242", "summary": "Arbitrary airflow.* class instantiation on the API server via the XCom deserialize endpoint", "details": "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": [{"ranges": [{"type": "SEMVER", "events": [{"introduced": "0"}, {"fixed": "3.3.1"}]}]}], "references": [{"type": "WEB", "url": "https://github.com/apache/airflow/pull/69378"}, {"type": "WEB", "url": "https://lists.apache.org/thread/dm0520yhh4mn7qknyoh45r2w6c5qg2mg"}]}