CVE-2026-6453: 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 cubewpremoverelation() AJAX function, specifically the use of wpunslash() on the relationid parameter before interpolating it directly into a raw SQL query without using $wpdb->prepare(). The wpunslash() call explicitly removes the backslash escaping that WordPress's wpmagicquotes() adds to all $POST data, neutralizing the only layer of SQL injection protection. The sanitizetextfield() 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.