CVE-2026-33264 Apache Airflow: DAG author RCE on webserver via unrestricted import_string() in BaseSerialization.deserialize()
A DAG author can achieve remote code execution on the Airflow API Server or Scheduler by embedding a malicious trigger in a serialized DAG.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33264?
CVE-2026-33264 is a critical unsafe deserialization vulnerability in Apache Airflow, published on 7 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-502
Which versions are affected by CVE-2026-33264?
4 open source packages ship an affected version, including apache-airflow and airflow. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
apache-airflow PyPI | All versions | 3.3.0 |
apache-airflow PyPI | All versions | 3.3.0 |
apache-airflow PyPI | All versions | 3.3.0 |
airflow Bitnami | All versions | 3.3.0 |
Products include Apache Airflow.
How do I fix CVE-2026-33264?
Upgrade apache-airflow to 3.3.0 or later.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-33264 being exploited?
There is no known exploitation of CVE-2026-33264 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-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
- CVE-2022-38649 Apache Airflow Pinot provider allowed Command Injection
Sources
Also known as BIT-airflow-2026-33264, CLEANSTART-2026-VP80273, ECHO-6322-53ef-9b9b, GHSA-2943-9672-r45w, MINI-7fwf-324x-vj47, MINI-fx8v-h2v8-p4cw and 1 more.