Fastcache by Host.it <= 1.7.5 - Missing Authorization to Authenticated (Subscriber+) Arbitrary .htaccess Page-Cache Block Modification via updateSettings() admin_action_update Hook

The Fastcache by Host.it plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 1.7.5. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with subscriber-level access and above, to add or remove the plugin's page-cache rewrite rules in the site's root .htaccess file.