CVE-2025-66221 (GCVE-0-2025-66221)
Vulnerability from cvelistv5
Published
2025-11-29 02:28
Modified
2025-12-01 15:35
Severity ?
6.3 (Medium) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CWE
  • CWE-67 - Improper Handling of Windows Device Names
Summary
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.
References
Impacted products
Vendor Product Version
pallets werkzeug Version: < 3.1.4
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