Apache Airflow's serialization layer reconstructed exception nodes by calling...
High8.8CVE-2026-58076 · Published Aug 12, 2026 · updated Sep 28, 2026
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 upgrad...
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| apache-airflow PyPI | >= 3.3.0, < 3.3.1 | 3.3.1 |
Details and references
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`.
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Severity from
- the CVSS score
- Also known as
- BIT-airflow-2026-58076, CVE-2026-58076
More Apache Airflow advisories
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|---|---|---|---|
| Aug 12 | Apache Airflow's Backfill API authorized a request against a Dag id supplied by... High7.5Aug 12 | High7.5 | 3.3.1 |
| Aug 12 | Apache Airflow wrote Variable values and Connection `extra` contents to the...Medium6.5Aug 12 | Medium6.5 | 3.3.1 |
| Aug 12 | Apache Airflow's Task SDK did not mask the contents of a Variable whose JSON...Medium6.5Aug 12 | Medium6.5 | 3.3.1 |
| Aug 12 | Apache Airflow's asset materialization endpointMedium6.5Aug 12 | Medium6.5 | 3.3.1 |
| Aug 12 | Apache Airflow's Task SDK rebuilt a `Callback` object from serialized data by...High8.8Aug 12 | High8.8 | 3.3.1 |
| Aug 12 | Apache Airflow's environment-variable secrets backend resolved a team-scoped...Medium5.4Aug 12 | Medium5.4 | 3.3.1 |