206
How are people discovering random subdomains on my server? (lemmy.blahaj.zone)
submitted 10 months ago by to c/selfhosted@lemmy.world
74 comments fedilink hide all child comments
 

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/

you are viewing a single comment's thread
view the rest of the comments
[–] [B] 57 points 10 months ago* (last edited 10 months ago) (2 children)

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:

Fewer Letters More Letters
CA (SSL) Certificate Authority
DNS Domain Name Service/System
IP Internet Protocol
SSL Secure Sockets Layer, for transparent encryption
TLS Transport Layer Security, supersedes SSL
VPN Virtual Private Network
VPS Virtual Private Server (opposed to shared hosting)

7 acronyms in this thread; the most compressed thread commented on today has 16 acronyms.

[Thread #990 for this comm, first seen 11th Jan 2026, 01:25] [FAQ] [Full list] [Contact] [Source code]

  • permalink
  • fedilink
  • source
  • hideshow 2 child comments
    •