CVE-2026-27199 Werkzeug safe_join() allows Windows special device names

Werkzeug is a comprehensive WSGI web application library. Versions 3.1.5 and below, the safejoin function allows Windows device names as filenames if preceded by other path segments. This was previously reported as GHSA-hgf8-39gv-g3f2, but the added filtering failed to account for the fact that...