werkzeug

Werkzeug’s safe_join() has a new Windows‑specific wrinkle: a recently assigned CVE shows the function can still resolve paths that end with legacy Windows device names when those names are embedded inside multi‑segment paths, allowing a remote request handled by send_from_directory() to open a...

A subtle but important security gap in Werkzeug’s path-joining logic has resurfaced: attackers can craft filenames that exploit Windows’ legacy device-name semantics and cause web servers using Werkzeug’s safe_join/send_from_directory helpers to hang. This vulnerability, tracked as...

A deceptively small parsing flaw in the popular Python WSGI utility library Werkzeug can be turned into a powerful denial-of-service weapon: specially crafted multipart/form-data uploads that start with a carriage return (CR) or line feed (LF), followed by megabytes of data without additional...

The Werkzeug safe_join vulnerability tracked as CVE-2025-66221 lets Windows-only special device names (for example, CON, AUX, NUL, COMx, LPTx) slip past path validation and be treated like ordinary files — a behavior that allowed web endpoints using send_from_directory to open a device path and...