CVE-2026-33264

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.

Score

CVSS 3.1 9.8 Critical

Status

Analyzed - security@apache.org

Published

2026-07-07

Last modified

2026-10-25

Weaknesses

CWE-502

Affected products

• Airflow (Apache)
• Apache Airflow (Apache Software Foundation)

References

• https://github.com/apache/airflow/pull/66002
• https://github.com/apache/airflow/pull/68528
• https://lists.apache.org/thread/otvdw8qt2y7xy2n5nq9xby9ky4rf5ltj
• http://www.openwall.com/lists/oss-security/2026/07/07/1