CVE-2026-40861CWE-59

Apache Airflow: Arbitrary File Read via Log Symlink following in FileTaskHandler

Medium · published June 1, 2026

CVSS v3.1
6.5
EPSS
1%
Percentile
54.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00758 · 54.7th percentile
Weakness
CWE-59 · Improper Link Resolution Before File Access ('Link Following')
Published
2026-06-01T07:55Z
EPSS history
Timeline
  • 01 JUN 07:55Z
    Apache Airflow: Arbitrary File Read via Log Symlink following in FileTaskHandler
    cvelistv5