This is where I get rankled.
In IT land, everything needs a valid certificate. The printer, the server, the hypervisor, the load balancer, the WAP’s UI, everything. That said, most things don’t require a publicly valid certificate.
Perhaps Intermediate CA is the wrong phrase for what I’m looking for. Ideally it would be a device that does a public DNS-01 validation for a non-wildcard certificate, thus granting it legitimacy. It would then crank out certificates for internal devices only, which would be trusted via the Root CA but without requiring those devices to talk to the internet or use a wildcard certificate. In other words, some sort of marker or fingerprint that says “This is valid because I trust the root and I can validate the internal intermediary. If I cannot see the intermediary, it is not valid.”
The thinking goes is that this would allow more certificates to be issued internally and easily, but without the extra layer of management involved with a fully bespoke internal CA. Would it be as secure as that? No, but it would be SMB-friendly and help improve general security hygiene instead of letting everything use HTTPS with self-signed certificate warnings or letting every device communicate to the internet for an HTTP-01 challenge.
If I can get PKI to be as streamlined as the rest of my tech stack internally, and without forking over large sums for Microsoft Server licenses and CALs, I’d be a very happy dinosaur that’s a lot less worried about tracking the myriad of custom cert renewals and deployments.