Description

Werkzeug is a comprehensive WSGI web application library. Prior to version 3.1.5, Werkzeug's safe_join function allows path segments with Windows device names that have file extensions or trailing spaces. On Windows, there are special device names such as CON, AUX, etc that are implicitly present and readable in every directory. Windows still accepts them with any file extension, such as CON.txt, or trailing spaces such as CON. This issue has been patched in version 3.1.5.

INFO

Published Date :

2026-01-08T18:34:05.390Z

Last Modified :

2026-01-08T18:50:34.504Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-21860 vulnerability.

Vendors Products
Microsoft
  • Windows
Palletsprojects
  • Werkzeug
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-21860.

URL Resource
https://github.com/pallets/werkzeug/commit/7ae1d254e04a0c33e241ac1cca4783ce6c875ca3 cve-icon cve-icon
https://github.com/pallets/werkzeug/security/advisories/GHSA-87hc-h4r5-73f7 cve-icon cve-icon
Login to claim this CVE

CVSS Vulnerability Scoring System

Detailed values of each vector for above chart.
Attack Vector
Attack Complexity
Attack Requirements
Privileges Required
User Interaction
VS Confidentiality
VS Integrity
VS Availability
SS Confidentiality
SS Integrity
SS Availability