You can disable cpanel/WHM login authentication by following the below steps.
1. Login to the server as root.
2. Edit the cpanel config file and set skiphttpauth=1
3. Please run ‘/usr/local/cpanel/whostmgr/bin/whostmgr2 –updatetweaksettings‘ to update the settings.
You can also disable the same via WHM. Follow the steps to make the changes
1. Login to your WHM/Cpanel server
2. Goto Main >> Server Configuration >> Tweak Settings
3. Set the value to OFF in the ‘Enable HTTP Authentication’
4. Save it.
Thank you 😛