I don't know how effective and quick to respond but there is a way to report malware [1]
Extracting from the page
> Which category of abuse to select > Phishing & Malware
Extracting from the page
> Which category of abuse to select > Phishing & Malware
Failing that:
> If Cloudflare is listed as the registrar on an ICANN WHOIS listing, you also can email reports related to our registrar services to registrar-abuse@cloudflare.com