Domain Control Validation (DCV) is used for checking the user who controls the domain before issuing an SSL certificate. Both the cPanel Market SSL Provider and AutoSSL uses files in a website’s document root (on most cPanel accounts: /home/user/public_html/) to verify that the server requesting the SSL controls the domain. The modifications on the Comodo will be reflected on the very core of cPanel’s DCV.
Comodo DCV Updates
The list of things Comodo is changing includes both the contents of the file and the directory in which it will be looking. Rather than looking in a website’s document root directly, it will now look inside a folder named “.well-known” inside the document root.
For example, right now the DCV check will look for HTTP(S)://fully.qualified.name/<filename.txt>. After the change is released, the DCV check will look for HTTP(S)://fully.qualified.name/. well-known/pki-validation/<filename.txt> to validate the domain.