In cPanel & WHM version 11.40 and earlier, visitors who accessed a website via https without an SSL configuration saw a connection error. 

In cPanel & WHM version 11.42 and later, we modified Apache's configuration to properly use service subdomains (proxy subdomains) with SSL.

In cPanel & WHM version 62 and later, cPanel & WHM enables SNI functionality by default for SSL certificates on service subdomains (proxy subdomains). SNI allows multiple SSL certificates to use a single IP address and port number.

Due to these changes, Apache uses cPanel's service SSL certificate to secure websites that do not have an SSL certificate. Visitors to sites without an SSL certificate may see an SSL warning, because Apache used cPanel's service SSL certificate to secure the site.

How to bypass the use of service subdomains (proxy subdomains) and the cPanel service SSL certificate

We do not recommend that you bypass your server's service subdomain (proxy subdomain) configuration.

To prevent the use of the cPanel service SSL certificate for the cpanel, whm, webdisk, and webmail subdomains, you must perform the following steps:

  1. Disable the Service subdomains setting in the Domains section of WHM's Tweak Settings interface (WHM >> Home >> Server Configuration >> Tweak Settings).

    In cPanel & WHM version 76, we renamed the Proxy Subdomains setting to Service Subdomains.

  2. Use cPanel's Subdomains interface (cPanel >> Home >> Domain >> Subdomains) to manually create each service's subdomain (for example, cpanel, whm, webdisk, and webmail).
  3. Redirect each service's subdomain to the appropriate secure URL and port as follows:

    cPanelcpanel.example.com https://example.com:2083
    WHM whm.example.com
    Web Disk webdisk.example.com https://example.com:2078
    Webmail webmail.example.com https://example.com:2096

When you navigate to webmail.example.com, the server redirects you to https://example.com:2096  and uses the example.com domain's SSL certificate to secure the connection.

Additional documentation