I generated 16 character (upper/lower) subdomain and set up a virtual host for it in Apache, and within an hour was seeing vulnerability scans.
How are folks digging this up? What’s the strategy to avoid this?
I am serving it all with a single wildcard SSL cert, if that’s relevant.
Thanks
Edit:
- I am using a single wildcard cert, with no subdomains attached/embedded/however those work
- I don’t have any subdomains registered with DNS.
- I attempted dig axfr example.com @ns1.example.com returned zone transfer DENIED
Edit 2: I’m left wondering, is there an apache endpoint that returns all configured virtual hosts?
Edit 3: I’m going to go through this hardening guide and try against with a new random subdomain https://www.tecmint.com/apache-security-tips/


Isnt security mostly achieved by heavy obscurity? A password secures because other people dont know what it is, it is obscured.
They’re not the same.
Hiding an unlocked treasure chest in the forest is obscurity. Sure, you might be the only one who knows it’s there at first but eventually someone might come across it.
Having a vault at a bank branch is security - everyone knows there’s a vault there, but you’ll be damned if you’re going to get into it when you’re not authorized.
Good passwords, when implemented correctly, use hashing (one way encryption) to provide security. It’s not obscured, people know you need a password to access the thing (in our example)
In cryptography, there’s a difference between “secrets” (like passwords and encryption keys), and hiding / obscuring something (like steganography or changing your web server to run on a different port)