CVE-2026-40861 (GCVE-0-2026-40861)

Vulnerability from cvelistv5 – Published: 2026-06-01 07:55 – Updated: 2026-06-02 16:42
VLAI
Title
Apache Airflow: Arbitrary File Read via Log Symlink following in FileTaskHandler
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-02 16:33 UTC
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache Airflow Affected: 0 , < 3.2.2 (semver)
Create a notification for this product.
Credits
Silas Boch Lakshmikanthan K (letchupkt) Jarek Potiuk
Show details on NVD website
To clipboard 

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