{"id":"GHSA-8prw-8m6x-8w6f","summary":"Apache Airflow exception-node deserialization permits arbitrary callable execution","details":"Apache Airflow's serialization layer reconstructed exception nodes by calling `import_string()` on a class name taken from the serialized blob and instantiating it with arguments from the same blob, with no restriction on what could be imported. An operator's `executor_config` reaches that branch, so a Dag author could place a value there that causes an arbitrary callable to be imported and invoked -- for example `subprocess.check_output`, or `builtins.eval` on the `builtins`-prefixed variant. The code runs in the **Scheduler**, which reconstructs serialized Dags in its normal loop with no request involved, and in the **API server**, on any authenticated read of the Dag such as `GET /api/v2/dags/{dag_id}/details`. Both are components the Airflow security model states must never execute Dag-author code, and both hold the metadata database credentials and the JWT signing secret. No non-default configuration is required. This is a **different sink from CVE-2026-33264**, which covered only the trigger branch of the same deserializer: deployments that upgraded in response to that advisory are still affected through the exception branch and must upgrade again. Users are advised to upgrade to apache-airflow 3.3.1 or later, which restricts the imported class to a subclass of `BaseException`.","aliases":["BIT-airflow-2026-58076","CVE-2026-58076","PYSEC-2026-3991"],"modified":"2026-10-02T23:40:41.994276070Z","published":"2026-08-12T18:31:17Z","database_specific":{"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2026-10-02T23:12:35Z","nvd_published_at":"2026-08-12T16:17:08Z","cwe_ids":["CWE-502"]},"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58076"},{"type":"WEB","url":"https://github.com/apache/airflow/pull/68511"},{"type":"WEB","url":"https://github.com/apache/airflow/commit/3a08a3d7792335ac9456cd44c92d8de3ae0d6ec1"},{"type":"WEB","url":"https://github.com/apache/airflow/commit/560f117525d201ed64327c4185050705339e07b1"},{"type":"PACKAGE","url":"https://github.com/apache/airflow"},{"type":"WEB","url":"https://github.com/apache/airflow/releases/tag/3.3.1"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/apache-airflow/PYSEC-2026-3991.yaml"},{"type":"WEB","url":"https://lists.apache.org/thread/t81p688t15jozxsng8521o60nh2kfsos"},{"type":"WEB","url":"https://www.cve.org/CVERecord?id=CVE-2026-33264"}],"affected":[{"package":{"name":"apache-airflow","ecosystem":"PyPI","purl":"pkg:pypi/apache-airflow"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.3.0"},{"fixed":"3.3.1"}]}],"versions":["3.3.0","3.3.1rc1","3.3.1rc2"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-8prw-8m6x-8w6f/GHSA-8prw-8m6x-8w6f.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}