WP Review Slider Pro <= 12.7.2 - Unauthenticated SQL Injection via 'notinstring' Parameter

Summary

The WP Review Slider Pro plugin for WordPress is vulnerable to SQL Injection via the 'notinstring' parameter of the wprp_load_more_revs AJAX action in versions up to, and including, 12.7.2. The parameter is read via $_POST['notinstring'] and passed through sanitize_text_field() — which strips HTML and whitespace but does not provide SQL safety. The value is then concatenated directly into a numeric/unquoted `AND id NOT IN (...)` clause and executed via $wpdb->get_results() without $wpdb->prepare() or intval() casting. Because the value sits in an unquoted numeric context, WordPress's wp_magic_quotes protection (which only escapes embedded quotes) is ineffective. The AJAX hook is registered via wp_ajax_nopriv_wprp_load_more_revs, and the required check_ajax_referer nonce is publicly available via wp_localize_script on any frontend page that renders the plugin shortcode, so an unauthenticated attacker who can reach a public page hosting the plugin can extract arbitrary data from the database via blind/time-based injection.