u/GnuHost

https://support.cpanel.net/hc/en-us/articles/40073787579671-Critical-Vulnerability-with-cPanel-WHM-Login-Authentication

The recommended solution is to close ports 2083 and 2087

Refer to the cPanel article for the latest solution, currently the recommendation is to close all cPanel-related ports and disable proxy/service subdomains

A patch has been released! Run /scripts/upcp now