Provide references for CVE-2021-4391.
Where can I find more information about CVE-2021-4391?
References are available at: https://www.wordfence.com/threat-intel/vulnerabilities/id/2da322ea-0206-4838-8ac4-9dd201bb00bc?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/browser/woo-gift-cards-lite/tags/2.1.2/admin/class-woocommerce-gift-cards-lite-admin.php?rev=2549904#L461.