The WP Fastest Cache plugin through 0.8.9.0 for WordPress allows remote attackers to delete arbitrary files because wp_postratings_clear_fastest_cache and rm_folder_recursively in wpFastestCache.php mishandle ../ in an HTTP Referer header.
https://www.wpfastestcache.com/
https://wordpress.org/plugins/wp-fastest-cache/#developers
https://wordpress.org/plugins/wp-fastest-cache/
https://plugins.trac.wordpress.org/browser/wp-fastest-cache/trunk/wpFastestCache.php