WP-Optimize <= 4.5.2 - Authenticated (Author+) Arbitrary File Deletion via 'original-file' Post Meta

The WP-Optimize – Cache, Compress images, Minify & Clean database to boost page speed & performance plugin for WordPress is vulnerable to arbitrary file deletion due to insufficient file path validation in the unscheduled_original_file_deletion function in all versions up to, and including, 4.5.2 This makes it possible for authenticated attackers, with author-level access and above, to delete arbitrary files on the server, which can easily lead to remote code execution when the right file is deleted (such as wp-config.php). This is possible because 'original-file' is a public (non-protected) meta key — it does not begin with an underscore — allowing Authors to freely create or modify it on their own attachment posts via the standard Edit Media form or the REST API.