CVE-2026-67587 Apache Airflow: DAG-author remote code execution on the Scheduler via a Serde `Callback` deserialization gadget
A DAG author can achieve remote code execution on the Apache Airflow Scheduler by exploiting a deserialization gadget in the Task SDK.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-67587?
CVE-2026-67587 is a high-severity unsafe deserialization vulnerability in Apache Airflow, published on 12 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Apache Airflow's Task SDK rebuilt a `Callback` object from serialized data by re-running its constructor, which imports the module named by the stored callback path. Because `SyncCallback` is itself an Airflow class it passes the default `allowed_deserialization_classes` allow-list, so tightening that setting does not help. A Dag author — who controls a task instance's `next_kwargs` through the task execution API — can therefore cause an arbitrary module to be imported inside the scheduler process, when the scheduler's `awaiting_input` timeout sweep deserializes that value. No non-default configuration is required; the sweep runs unconditionally. Versions before 3.3.0 are not affected: the class existed, but the scheduler sweep that reaches it did not. This is a separate code path from CVE-2026-58076 and CVE-2026-67260, which cover different gadgets reaching deserialization — applying either of those fixes does not address this one. Users are advised to upgrade to apache-airflow 3.3.1 or later.
Weakness: CWE-502
Which versions are affected by CVE-2026-67587?
4 open source packages ship an affected version, including apache-airflow and airflow. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
apache-airflow PyPI | From 3.3.0 | 3.3.1 |
apache-airflow PyPI | From 3.3.0 | 3.3.1 |
apache-airflow PyPI | From 3.3.0 | 3.3.1 |
airflow Bitnami | From 3.3.0 | 3.3.1 |
Products include Apache Airflow.
How do I fix CVE-2026-67587?
Upgrade apache-airflow to 3.3.1 or later.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-67587 being exploited?
There is no known exploitation of CVE-2026-67587 in the wild and no public exploit code.
Other vulnerabilities in Apache Airflow
- CVE-2020-13927 Apache Airflow's Experimental API Authentication Bypass
- CVE-2020-11978 Apache Airflow Command Injection
- CVE-2026-33264 Apache Airflow: DAG author RCE on webserver via unrestricted import_string() in BaseSerialization.deserialize()
- CVE-2023-25754 Apache Airflow: Privilege escalation using airflow logs
- CVE-2023-22884 Apache Airflow, Apache Airflow MySQL Provider: Arbitrary file read via MySQL provider in Apache Airflow
Sources
Also known as BIT-airflow-2026-67587, GHSA-2qjv-p2gc-mjg2, MINI-j8jm-4p84-qvfx, PYSEC-2026-3708.