The lists are out there.

If you read “Well, hello there.”, you probably know I was curious where that traffic was coming from and couldn’t leave it alone. I finally figured out one answer.

It’s ICANN’s Centralized Zone Data Service.

That’s where people can get a list of all domains registered under many top-level domains, updated every 24 hours. I had no idea it existed before today.

There are even special Unicode TLDs like 微博.

Mystery solved. Tell Scooby Doo not to come.

There’s another wrinkle, though: Certificate Transparency logs can reveal domains, too.