CVE-2026-34538
Apache Airflow 3.0.0 – 3.2.0
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:NSummary
CVE-2026-34538 is a medium-severity Exposure of Resource to Wrong Sphere (CWE-668) vulnerability in Apache Airflow. Its CVSS base score is 6.5 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Information Repositories (T1213); ranked at the 49th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-20878
Vulnerability Data
Apache Airflow versions 3.0.0 through 3.1.8 DagRun wait endpoint returns XCom result values even to users who only have DAG Run read permissions, such as the Viewer role.This behavior conflicts with the FAB RBAC model, which treats XCom as a…
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separate protected resource, and with the security model documentation that defines the Viewer role as read-only. Airflow uses the FAB Auth Manager to manage access control on a per-resource basis. The Viewer role is intended to be read-only by default, and the security model documentation defines Viewer users as those who can inspect DAGs without accessing sensitive execution results. Users are recommended to upgrade to Apache Airflow 3.2.0 which resolves this issue.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Vulnerability exposes XCom data (information repository) to users lacking intended permissions via API endpoint authorization flaw.
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
Mitigating Controls (NIST 800-53 r5) AI
Directly enforces per-resource authorization so the DagRun wait endpoint cannot return XCom values to principals that only hold DAG Run read permission.
Ensures the Viewer role receives only the minimal privileges defined by the FAB RBAC model and never obtains implicit access to protected XCom execution results.
Mediates information flows between the DagRun endpoint and XCom resources so that read-only DAG Run access cannot leak sensitive execution data.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Enforcing least-privilege authorizations directly prevents resources from being exposed outside their intended control sphere.
Network segmentation and unauthorized-access protections reduce the chance of resources being reachable by the wrong sphere.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Placing systems of differing trust levels into separate domains prevents resources from being placed in a sphere where they are reachable by unintended actors.
Requiring owners to manage the full asset life cycle and remove assets from the inventory upon secure disposal helps prevent resources from being inadvertently exposed outside their intended security sphere.