CVE-2026-102598

Werkzeug is a comprehensive WSGI web application library. Prior to 3.1.9, the safe_join function used by send_from_directory can allow a NUL: special-device path because safe_join checks the Windows device name without first removing an empty NTFS ADS marker. The trigger is that an application runs on Windows with NTFS and serves a user-specified path ending in a special device name such as NUL:. The attack mechanism is that a requested path ends in a Windows special device name with an empty ADS marker. The impact is that the special device opens successfully and the file read hangs indefinitely. This issue is fixed in version 3.1.9.

CVSS

No CVSS.

References

Link	Resource
https://github.com/pallets/werkzeug/commit/8d77320bcdf3a34941ec06dcf16b03c065cd21b6
https://github.com/pallets/werkzeug/pull/3309
https://github.com/pallets/werkzeug/releases/tag/3.1.9
https://github.com/pallets/werkzeug/security/advisories/GHSA-g6x2-hccm-hh4m

Configurations

No configuration.

History

29 Sep 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-29 16:17

Updated : 2026-09-30 19:38

NVD link : CVE-2026-102598

Mitre link : CVE-2026-102598

CVE.ORG link : CVE-2026-102598

JSON object : View

Products Affected

No product.

CWE

CWE-67

Improper Handling of Windows Device Names

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