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…
Does this matter?
Lower severity and a low EPSS score (0.69%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.69% probability · 51th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-59
- Affected
- apache/airflow
- Source
- security@apache.org
References
- https://github.com/apache/airflow/pull/65325Issue Tracking, Patch
- https://lists.apache.org/thread/823334db2559xjlwt59gpzjz47thnsclMailing List, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2026/05/31/1Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.