Selfhosted

60210 readers

970 users here now

A place to share alternatives to popular online services that can be self-hosted without giving up privacy or locking you into a service you don't control.

Rules:

Detailed Rules Post

Be civil.
No spam.
Posts are to be related to self-hosting.
Don't duplicate the full text of your blog or readme if you're providing a link.
Submission headline should match the article title.
No trolling.
Promotion posts require active participation, with an account that is at least 30 days old. F/LOSS without a paywall has exceptions, with requirements. See the rules link for details.

Resources:

selfh.st Newsletter and index of selfhosted software and apps
awesome-selfhosted software
awesome-sysadmin resources
Self-Hosted Podcast from Jupiter Broadcasting

Any issues on the community? Report it using the report flag.

Questions? DM the mods!

founded 3 years ago

MODERATORS

curbstickle@anarchist.nexus

curbstickle_lw@lemmy.world

215

How are people discovering random subdomains on my server? (lemmy.blahaj.zone)

submitted 5 months ago* (last edited 5 months ago) by BonkTheAnnoyed@lemmy.blahaj.zone to c/selfhosted@lemmy.world

85 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

[–] eli@lemmy.world 4 points 5 months ago* (last edited 5 months ago)

I run my webservers behind a pfsense firewall with ssl offloading(using a wildcard cert) with a static IP and use Haproxy to have sub-domain's go to individual servers. Even though I've seen my fair share of scans, I only ever expose port 443 and keep things updated.

Recently though someone on here mentioned routing everything over Tailscale via a VPS. I didn't want to pay for a VPS and frankly can't even find one that is reasonably priced in the US(bandwidth limits mainly), so I threw Tailscale onto my pfsense, setup split-dns on Tailscale's admin panel with my domain name, and then reconfigured Haproxy to listen on my Tailscale interface. Even got IPv6 working(huge pain due to a bug it seems). Oh and setup pfblocker.

My current plan is I'm going to run my webservers behind Tailscale and keep my game servers public and probably segment those servers to a different vlan/subnet/dmz/whatever. And maybe just have a www/blog landing page that is read only on 443 and have it's config/admin panel accessible via my tailscale only.

Anyway, back on topic. I run my game servers and I don't advertise them out anywhere(wildcard cert) and do whitelist only, yet I still see my minecraft servers get hit constantly on port 25565.

So not much you can do except minimize exposure as much as possible.