Did You Know? All Subdomains Are Public If You Have an SSL Certificate!

When you secure your website with an SSL certificate, all subdomains are publicly visible, even if you don’t actively use them, because SSL certificates are logged in public records, making it easy for anyone to find your subdomains through online tools.Make sure your unused or forgotten subdomains software is locked down tight.

Staying aware of your subdomains helps keep your and  your clients  data safe and protected

You can test yourself here: https://subdomainfinder.c99.nl/