CVE-2026-40861

A Dag author could either (a) create a symlink under their task's log directory pointing to an arbitrary file readable by the API server process (read-path attack — e.g. `/etc/passwd` or `airflow.cfg`) or (b) supply a `task_id` containing `..` sequences accepted by the Task SDK's `KEY_REGEX` (write-path attack), and in both cases the FileTaskHandler resolves the log path outside the configured `base_log_folder`, leaking or overwriting arbitrary files. Only affects deployments where the worker log folder is shared with the API server. Users are advised to upgrade to `apache-airflow` 3.2.2 or later. As a defense-in-depth mitigation, deploy the worker and API server with separate log volumes so that worker-controlled paths cannot reach the API server's filesystem.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/apache/airflow/pull/65325	Issue Tracking Patch
https://lists.apache.org/thread/823334db2559xjlwt59gpzjz47thnscl	Mailing List Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/05/31/1	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-01 09:16

Updated : 2026-07-21 19:10

NVD link : CVE-2026-40861

Mitre link : CVE-2026-40861

CVE.ORG link : CVE-2026-40861

JSON object : View

Products Affected

apache

airflow

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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