Yes, any attacker can search for your site's DNS history and try to find the real ip there. For example you can get the history for some sites using this servic

Yes, any attacker can search for your site's DNS history and try to find the real ip there. For example you can get the history for some sites using this service: https://www.netcraft.com/ https://www.netcraft.com/ The good thing is that there's a real fix for this and is to configure your server's firewall to only accept requests from Cloudfare's ips.