RW Elephant Rental Inventory <= 2.3.13 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Modification via 'toggle_cache' AJAX Action

The RW Elephant Rental Inventory plugin for WordPress is vulnerable to Missing Authorization in all versions up to and including 2.3.13. This is due to a missing capability check on the toggle_cache() function which is hooked to the wp_ajax_toggle_cache AJAX action. The function also lacks nonce verification. This makes it possible for authenticated attackers, with Subscriber-level access and above, to toggle the plugin's cache setting on or off by sending a POST request to admin-ajax.