Hummingbird < 3.4.2 - Unauthenticated Path Traversal

Description

The plugin does not validate the generated file path for page cache files before writing them, leading to a path traversal vulnerability in the page cache module.

This allows an attacker to:
- Enumerate file system directories where the user who starts the web server process has write access.
- Crash the server by generating an endless number of unique queries, which will be saved outside wphb-cache, thus preventing the purge cache functionality from removing cached files from the server file system.
- Disable some web application functionalities (like breaking the redirections) because the plugin creates empty index.html in the directory where it saves the cache file.
- Write cache files, including `index.html` to the web application directories on the same server, which may significantly affect availability.