CubeWP Framework <= 1.1.30 - Authenticated (Subscriber+) SQL Injection via 'relation_id' Parameter

The CubeWP Framework plugin for WordPress is vulnerable to SQL Injection in all versions up to and including 1.1.30. This is due to insufficient input sanitization in the cubewp_remove_relation() AJAX function, specifically the use of wp_unslash() on the relation_id parameter before interpolating it directly into a raw SQL query without using $wpdb->prepare(). The wp_unslash() call explicitly removes the backslash escaping that WordPress's wp_magic_quotes() adds to all $_POST data, neutralizing the only layer of SQL injection protection. The sanitize_text_field() function applied afterward offers no SQL protection. This makes it possible for authenticated attackers, with subscriber-level access and above, to append additional SQL queries to the existing query.