Securing SSL Certificates
Does an SSL certificate secure both www.coolexample.com and coolexample.com?
Yes, an SSL certificate secures the common name (domain name) listed in the certificate, with or without the "WWW" prefix.
NOTE: Until renewed, certificates issued prior to December 2006 only secure the exact, fully-qualified domain entered as the common name in the Certificate Signing Request (CSR). Thus, a certificate that secures "www.coolexample.com" does not secure the "coolexample.com."
The Subject Alternative Names (SANs) do not receive the same treatment.
In the case of UCC certificates or "Multiple Domain Certificates," only the primary domain name is secured both with and without www.