Vulnerability · Published Jun 1, 2026 · Assigned by apache
CVE-2026-40861Apache Airflow: Arbitrary File Read via Log Symlink following in FileTaskHandler
Medium 6.5
In plain English
A medium-severity security flaw in Apache Airflow from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | apache-airflow | 3.2.2 | GHSA-89cj-xrpx-j79m |
| PyPI | apache-airflow | 3.2.2 | PYSEC-2026-181 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache Airflow | 0 – before 3.0.0 |
| Apache Software Foundation | Apache Airflow | 3.0.0 – before 3.2.2 |
Weakness: CWE-59 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N