Apache Airflow: Arbitrary airflow.* class instantiation on the API server via the XCom deserialize endpoint

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-59242
StatePUBLISHED
Assignerapache
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-08-12 16:17:09 UTC
Updated2026-08-12 17:17:28 UTC
DescriptionApache Airflow's XCom `GET /api/v2/{...}/xcomEntries/{key}?deserialize=true` endpoint passed a string-literal payload through `BaseXCom.deserialize_value` without the `_check_forbidden_xcom_keys` guard, allowing an authenticated API user with XCom write-and-read access to instantiate arbitrary `airflow.*` classes on the API server (CWE-502). An authenticated user who can write an XCom value and then read it back with `deserialize=true` triggers the unsafe instantiation. Users are advised to upgrade to apache-airflow 3.3.1 or later, which rejects reserved XCom serialization keys submitted as JSON string literals.

Risk And Classification

Primary CVSS: v3.1 5.4 MEDIUM from ADP

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Problem Types: CWE-502 | CWE-502 CWE-502: Deserialization of Untrusted Data

VersionSourceTypeScoreSeverityVector
3.1ADPDECLARED5.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
3.1134c704f-9b21-4f2e-91b3-4a467353bcc0Secondary5.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Apache Software Foundation Apache Airflow affected 3.3.1 semver Not specified

References

ReferenceSourceLinkTags
github.com/apache/airflow/pull/69378 [email protected] github.com
lists.apache.org/thread/dm0520yhh4mn7qknyoh45r2w6c5qg2mg [email protected] lists.apache.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: localhost-detect (@localhost-detect) (en)

CNA: Jarek Potiuk (en)

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report