{"schema_version": "1.6.1", "id": "CVE-2026-33264", "summary": "DAG author RCE on webserver via unrestricted import_string() in BaseSerialization.deserialize()", "details": "A bug in `BaseSerialization.deserialize()` allowed unrestricted `import_string()` of attacker-controlled class paths when the Scheduler / API Server loaded a serialized DAG: a DAG author could embed a malicious trigger into a DAG to gain remote code execution on the API Server / Scheduler process, crossing the Airflow security boundary that DAG-author code must never execute in those processes. Users are advised to upgrade to `apache-airflow` 3.3.0 or later. As a defense-in-depth mitigation, deployments where DAG-author trust is limited can restrict the `[core] allowed_deserialization_classes` config to a narrow allowlist.", "affected": [{"ranges": [{"type": "SEMVER", "events": [{"introduced": "0"}, {"fixed": "3.3.0"}]}]}], "references": [{"type": "WEB", "url": "https://github.com/apache/airflow/pull/66002"}, {"type": "WEB", "url": "https://github.com/apache/airflow/pull/68528"}, {"type": "WEB", "url": "https://lists.apache.org/thread/otvdw8qt2y7xy2n5nq9xby9ky4rf5ltj"}]}