Hummingbird <= 3.4.1 - Unauthenticated Path Traversal

The Hummingbird plugin for WordPress is vulnerable to Path Traversal in versions up to, and including, 3.4.1 via the page cache module, which doesn't validate file paths prior to saving them. This makes it possible for unauthenticated attackers to enumerate file directories, crash to server by sending cache files to an arbitrary location, and write cache files to arbitrary locations that may deny access to some resources.