The WP Fastest Cache plugin for WordPress is vulnerable to unauthorized cache deletion in versions up to, and including, 1.1.2 due to a missing capability check in the deleteCacheToolbar function . This makes it possible for authenticated attackers, with subscriber-level permissions and above, to delete the site's cache.
https://plugins.trac.wordpress.org/browser/wp-fastest-cache/trunk/wpFastestCache.php#L866