CVE-2026-33858

Apache Airflow: Unsafe Deserialization via Legacy Serialization Keys (__type/__var) Bypass in XCom API

Published Apr 13, 2026 CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed
Description
Dag Authors, who normally should not be able to execute code in the webserver context could craft XCom payload causing the webserver to execute arbitrary code. Since Dag Authors are already highly trusted, severity of this issue is Low.


Users are recommended to upgrade to Apache Airflow 3.2.0, which resolves this issue.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-mc4f-r875-v87w Apache Airflow: Unsafe Deserialization via Legacy Serialization Keys (__type/__var) Bypass in XCom API
History
Type Values Removed Values Added
CPEs cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:*
Type Values Removed Values Added
First Time appeared Apache
Apache airflow
Vendors & Products Apache
Apache airflow
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Dag Authors, who normally should not be able to execute code in the webserver context could craft XCom payload causing the webserver to execute arbitrary code. Since Dag Authors are already highly trusted, severity of this issue is Low. Users are recommended to upgrade to Apache Airflow 3.2.0, which resolves this issue.
Title Apache Airflow: Unsafe Deserialization via Legacy Serialization Keys (__type/__var) Bypass in XCom API
Weaknesses CWE-502
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
apache
Published
Updated
Nov 3, 2026, 6:54 AM
Reserved
Mar 24, 2026, 9:30 AM
Status
Analyzed
Published
Apr 13, 2026, 3:17 PM
Modified
Nov 3, 2026, 7:19 AM