Provide references for CVE-2021-4393.
Where can I find more information about CVE-2021-4393?
References are available at: https://www.wordfence.com/threat-intel/vulnerabilities/id/12ecf3d5-1457-405a-8856-517c7d2f2db1?source=cve, https://blog.nintechnet.com/25-wordpress-plugins-vulnerable-to-csrf-attacks/, https://blog.nintechnet.com/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/, https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-3/, https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-2/, https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/, https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-5/, https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-4/, https://plugins.trac.wordpress.org/changeset/2473569/ecommerce-product-catalog/trunk/modules/cart/includes/orders/includes/register-digital-orders.php.