CVE-2026-33264 Apache Software Foundation CVE debrief

Who should care

Users of Apache Airflow versions prior to 3.3.0 should upgrade to the latest version to mitigate this vulnerability. This includes operators, platform administrators, vulnerability management teams, and security teams who need to assess the impact and prioritize remediation.

Technical summary

The vulnerability exists in the `BaseSerialization.deserialize()` method, which allows unrestricted `import_string()` of attacker-controlled class paths. This can be exploited by a DAG author to embed a malicious trigger into a DAG, leading to remote code execution on the API Server / Scheduler process. The bug affects Apache Airflow versions prior to 3.3.0. To mitigate this vulnerability, users should 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. It is recommended that operators, platform administrators, vulnerability management teams, and security teams assess the impact and prioritize remediation. Evidence of the vulnerability's existence and details can be verified through official advisories and CVE records.

Defensive priority

High

Recommended defensive actions

• Upgrade to apache-airflow 3.3.0 or later
• Restrict the `[core] allowed_deserialization_classes` config to a narrow allowlist as a defense-in-depth mitigation
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance

Evidence notes

The CVE record was published on 2026-07-07T10:16:40.443Z and has not been modified since then. The NVD entry is currently Received. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the official advisory.

Official resources