I am thinking about transitioning a number of websites over to using a UC or Multiple Domain SSL certificate.
I guess I'm just wondering what the drawbacks are. So far the only ones I can find are that:
- they're not ideal if you don't want different domains identified with each other.
- because you have only one certificate instead of several, if one certificate gets compromised then it's a greater security risk
- there are some concerns about compatibility with older browsers, as well as some mobile browsers
We don't deal heavily with private information, just info like e-mail, name, organization, etc. We do collect credit card payments but the volume is very small. These certificates would be used mostly for logins.
Adding to what you've got up there:
I wouldn't give much weight to the security concern of key compromise; if your web server is breached and is hosting all of those sites, private keys for separate certificates will all be just as accessible to an attacker as a single alternate-name certificate's key would be.
Performance and updates must be considered;
https://casecurity.org/2014/02/26/pros-and-cons-of-single-domain-multi-domain-and-wildcard-certificates/