Security Vulnerability Report
中文
CVE-2025-66221 CVSS 5.3 MEDIUM

CVE-2025-66221

Published: 2025-11-29 03:16:00
Last Modified: 2025-12-03 15:27:49

Description

Werkzeug is a comprehensive WSGI web application library. Prior to version 3.1.4, Werkzeug's safe_join function allows path segments with Windows device names. On Windows, there are special device names such as CON, AUX, etc that are implicitly present and readable in every directory. send_from_directory uses safe_join to safely serve files at user-specified paths under a directory. If the application is running on Windows, and the requested path ends with a special device name, the file will be opened successfully, but reading will hang indefinitely. This issue has been patched in version 3.1.4.

CVSS Details

CVSS Score
5.3
Severity
MEDIUM
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Configurations (Affected Products)

cpe:2.3:a:palletsprojects:werkzeug:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:* - NOT VULNERABLE
Werkzeug < 3.1.4

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import requests target = 'http://target.com' path = '/static/..%5C..%5CAUX' response = requests.get(target + path)

References

Raw JSON Data

JSON
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