CVE-2026-86829: Apache Airflow: Deserialization of task-controlled XCom values in the Scheduler during dependency evaluation
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 0.3%
EPSS score, percentile 21.1 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- Not scored
The CVE record carries no CVSS score.
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
- Which versions are affected?
Affected
- before 3.4.0
Source: CISA KEV 2026.11.10, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
Description
Apache Airflow: Deserialization of task-controlled XCom values in the Scheduler during dependency evaluation
Apache Airflow's scheduler fully deserializes XCom values written by task code while evaluating task dependencies. A Dag author, who controls what a task writes to XCom, therefore controls data that is deserialized inside the scheduler process - a context the Airflow security model reserves for code installed by the Deployment Manager, above the worker-scoped execution capability a Dag author is documented to have. Deployments that treat Dag authors as less trusted than Deployment Managers are affected, and the scheduler must be evaluating a task dependency that reads a task-written XCom value. Users of apache-airflow are recommended to upgrade to version 3.4.0 or later, which restricts dependency evaluation to primitive XCom values.
Source: CVE List, as of . About the data.
What to do
Advisories and patches
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
Versions by product, as listed in the CVE record (1 product)
| Status | Versions |
|---|---|
| Affected | before 3.4.0 |
Versions not listed are: unaffected.
Source: CVE List, as of . About the data.
Weakness
CWE-502
- CWE-502: Deserialization of Untrusted Data
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.
Timeline
| Date | Event |
|---|---|
| CVE record published |
Known exploited Apache vulnerabilities
- CVE-2016-3081: Apache Struts Command Injection Vulnerability
- CVE-2026-34486: Apache Tomcat Missing Encryption of Sensitive Data Vulnerability
- CVE-2026-34197: Apache ActiveMQ Improper Input Validation Vulnerability
- CVE-2024-38475: Apache HTTP Server Improper Escaping of Output Vulnerability
- CVE-2025-24813: Apache Tomcat Path Equivalence Vulnerability