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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.03%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.03% probability · 62th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-502
- Affected
- apache/airflow
- Source
- security@apache.org
References
- https://github.com/apache/airflow/pull/66002Issue Tracking, Patch
- https://github.com/apache/airflow/pull/68528Issue Tracking, Patch
- https://lists.apache.org/thread/otvdw8qt2y7xy2n5nq9xby9ky4rf5ltjVendor Advisory, Mailing List
- http://www.openwall.com/lists/oss-security/2026/07/07/1Third Party Advisory, Mailing List
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.