Is CVE-2026-111421 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-111421 being exploited in the wild.

How severe is CVE-2026-111421?

Informational severity, published 9 November 2026.

Is there a fix for CVE-2026-111421?

Yes: fixed in apache-airflow 3.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-111421 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-111421?

Check whether you run Apache Airflow at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-111421: Apache Airflow Task Execution API XCom deserialization in dependency evaluation

CVE-2026-111421 · Severity: info · Published 2026-11-09

Apache Airflow is a workflow orchestration platform that manages task scheduling and execution. When the scheduler reads task metadata values (XCom) to determine task dependencies, it was unnecessarily deserializing untrusted data, allowing a DAG author to inject malicious serialized objects that instantiate arbitrary Airflow classes with attacker-controlled arguments when the API later displays those values. This bypasses a partial fix from an earlier CVE and requires upgrading to version 3.4.0.

Technologies: Apache Airflow. Vendors: Apache.

Quick answers

Is CVE-2026-111421 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-111421 being exploited in the wild.
How severe is CVE-2026-111421?: Informational severity, published 9 November 2026.
Which products and versions are affected?: Apache Airflow through 3.3.1.
Is there a fix for CVE-2026-111421?: Yes: fixed in apache-airflow 3.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-111421 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-111421?: Check whether you run Apache Airflow at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: apache-airflow 3.4.0 or later

Technical details

The vulnerability exists in how the scheduler's dependency evaluation reads XCom values through TaskInstance.xcom_pull → XComModel.deserialize_value, which calls json.loads with an XComDecoder object_hook that fully deserializes nested dicts with __classname__ keys, instantiating arbitrary Airflow classes. The scheduler only needs primitive values (boolean skip flags and task ID mappings), not deserialized objects. An incomplete prior fix (CVE-2026-59242) patched the API's direct write path but left the scheduler's read path vulnerable. The fix removes object reconstruction during scheduler-side dependency evaluation by using plain JSON deserialization for those reads only.

Affected products

Apache Airflow through 3.3.1

Timeline

2026-11-09: disclosed

References

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