Use SSL certificate intended for *.contoso.com on a stand alone server that is not part of contoso.com

Question

Suppose I purchase contoso.com from GoDaddy and also purchase a wildcard SSL certificate for *.contoso.com from GoDaddy. I now have a web server on xyz.contoso.com that I can secure with HTTPS using this certificate. Good!

Suppose I also have another website hosted on another server, that is not part of this contoso.com domain (or any domain), can I still use the same wild card certificate for this server, provided I take care of DNS to redirect abc.contoso.com to the IP address of this server ?

I think there are ways in different hosting providers to achieve this by paying for static public IP addresses, correct me if I'm wrong.

If this is possible, then am I just violating the licensing agreements of the SSL certificate as it was intended for one purpose but I'm using it for another (since I'm using it on a different domain) ?
The user is under the assumption that he is accessing some resource within contoso.com, while he is actually hitting a server that is not in contoso.com, but is owned by the same person as the owner of contoso.com.

Answer 1

I gather you intend to use a wildcard cert for *.mydomain.com across two servers with two public IPs and two different subdomains under the same domain name. This is a common scenario.

Provided that:

• The wildcard cert is appropriate for the new server. Which it seems like it is, given that both will share the xyz.mydomain.com convention and this very cert is working properly in your existing server.
• You provision the DNS entries to balance the queries as desired (you seem to already have taken that into consideration).

There seems to be no technical impediment for your certificates to work and be accepted.

However, consult your issuer's terms of service to rule out acceptable use policy issues. Wildcard certs are designed for just such a use case, however every vendor can enforce their own terms of service. A quick email to their support should solve this aspect.

Answer 2

Technically, you can only secure a single domain and its unlimited sub-domains using a Wildcard SSL Certificate.

When you generate your SSL Certificate and CSR, you were asked to add the domain name for which you need that wildcard cert.

As per SSL's terms and condition you can not change that domain name. You either need to cancel that certificate and issuer another one (only if it comes under money back guarantee period).

There is another real world solution to secure multiple domains and sub-domains under single certificate. And that is "Comodo Multi Domain Wildcard Certificate".

This allows you to secure up to 100 multiple domains and their sub-domains.

So, if you really wish to secure multiple domains and sub-domains under single certificate, this is a better option.