{"id":"CVE-2026-58076","aliases":["BIT-airflow-2026-58076","GHSA-8prw-8m6x-8w6f","PYSEC-2026-3991"],"url":"https://o3.security/vulnerability/CVE-2026-58076","summary":"Apache Airflow: Unguarded import_string() of airflow_exc_ser / base_exc_ser exception nodes in BaseSerialization.deserialize enables DAG-author RCE on Scheduler / API Server","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`.","published":"2026-08-12T15:40:59.934Z","modified":"2026-10-21T02:58:46.209768204Z","cvss":{"score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"epss":{"score":0.00484,"percentile":0.39804,"asOf":"2026-09-01"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"apache-airflow","fixedVersion":"3.3.1"}],"fix":{"url":"https://github.com/apache/airflow/pull/68511","label":"apache/airflow#68511"},"references":[{"type":"WEB","url":"https://pypi.python.org"},{"type":"WEB","url":"https://www.cve.org/CVERecord?id=CVE-2026-33264"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58076.json"},{"type":"ADVISORY","url":"https://lists.apache.org/thread/t81p688t15jozxsng8521o60nh2kfsos"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58076"},{"type":"FIX","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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T02:58:46.209768204Z"}}