Cyber Resilience

CVE-2026-40861

Medium

Published: 01 June 2026

Published
01 June 2026
Modified
02 June 2026
KEV Added
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Patch
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CVSS Score v3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0010 27.7th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-40861 is a medium-severity Link Following (CWE-59) vulnerability in Apache Airflow. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Local System (T1005); ranked at the 27.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)
CWE-59

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
attack.mitre.org →
T1552.001 Credentials In Files Credential Access
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.
attack.mitre.org →
Why these techniques?

Path traversal + symlink following enables direct arbitrary file read (e.g. configs or /etc/passwd) from the API server process.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v18.1

Affected Assets

apache
airflow
≤ 3.2.2

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References