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My Homelab Got Hacked - A Postmortem – Phunky Cafe (phunky.cafe)
submitted 2 months ago by to c/selfhosted@lemmy.world
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Welp. My Forgejo instance got popped with an RCE two days ago by CVE-2026-60004. Luckily, I noticed the following morning and had the day free to figure out what happened. Let's dive in!

As a homelab enthusiast, I found this a very interesting post. Here are my take aways from the post that I'm implementing myself:

  • Miner detection. I've updated monitoring rules to now watch the CPU on my hosts. If the same thing happened to me I would not have been alerted at all as I'm doing simple up / down monitoring. Fixed.
  • Access logging. I turned on access logging for my homelab Caddy instances.
  • Log retention. I have increased the amount and retention of my logging. The hope is this will help me reconstruct what happened after a breach.
  • Logs offsite. The VPS access logs now ride along with the normal backup process, which runs hourly. The homelab side still only gets caught by the weekly VM backup, so that's next.
  • Closed an open signup. My webtrees instance (genealogy) had self registration enabled, which is the same door this guy got hit through. Oops. Fixed.
  • Built a tool. log-inventory.sh, so "could I actually reconstruct what happened" is a command I run instead of a thing I assume.
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[–] 95 points 2 months ago (13 children)

I don't think I will ever be convinced to leave anything on my home network open to the internet no matter how convenient it is.

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  • [–] 36 points 2 months ago (3 children)

    It's fairly safe as long as you add a strong enough form of access control. For example if you put it behind a VPN, or a SSH tunnel, or require mTLS. Even a key in a custom HTTP header or Basic HTTP auth can be good enough if the key is strong enough.

    You can further decrease the probability of drive-by bots reaching a publicly exposed service by merely scanning IPs and ports if you use a reverse proxy and hide your service FQDNs and IP.

    You can do this by using TLS certs on wildcard domains rather than explicit domains, using explicit CNAMEs for the service subdomains rather than a wildcard domain, and keeping the A/AAAA records on an obfuscated subdomain rather than the base domain. If the bots can't figure out a FQDN they're not getting past the reverse proxy even if they find the IP and port.

    This is obfuscation not real security but it cuts down tremendously on bot hits.

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  • [–] 9 points 2 months ago

    I have knockd listening on one very high port number, and only after accessing that reverse proxy whitelists the source ip. Sure some scanners might do a full port scan and try http only after that, but FQDN is required too. Plus I have geo ip list blocking all but my country. Oh and Crowdsec. So far so good..

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  • [–] 9 points 2 months ago (6 children)

    I gave up , don't have the time to maintain it anymore. Changed DNS to make my domain point to local lan IP so everything still works but only at home.

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  • [–] 3 points 2 months ago (5 children)

    I wonder if the person who downvoted you thought you pointed your public DNS record to a 192.168 network, instead of making a change to your local DNS server like I'm assuming you did.

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  • [–] 2 points 2 months ago (4 children)

    If you want https it's gotta be a external DNS record anyway, might as well point to internal ips

    Depending on how paranoid your setup is not everything will use the DHCP provided DNS servers

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  • [–] 6 points 2 months ago (2 children)

    If you want https it's gotta be a external DNS record anyway

    Not sure what you mean by that, but off the top of my head, you can get certificates via challenges that prove DNS control (rather than checking if the DNS points to your server), and you can get wildcard certificates so you don't even have to expose the existence of subdomains.

    And that's ignoring the option of using your own CA, which only really works with your own devices, but for local access might be viable.

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  • [–] 1 point 3 weeks ago (1 child)

    So what you do is you have an external DNS that sharing your URL. You have the DNS point "myrealcoolurl.net" at 192.168.1.123. Now when anyone goes to "myrealcoolurl.net" the dns points them at 192.168.1.123 which worse case is their own router, if they are on your network though they get pointed at your server and are loving all your home hosted applications.

    Now you can get a wildcard TLS cert issued for "myrealcoolyrl.net" and apps in your home network can use https. Anyone outside your network still gets whatever 192.168.1.123 means for them in their home network

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  • [–] 2 points 3 weeks ago

    I'm a bit confused by what you're saying, because to my knowledge the DNS entry you're mentioning won't help with getting a certificate at all. Challenges will typically require either having the DNS entry point to a publicly reachable website (doesn't get you wildcard) or proving the ability to modify records for the domain by adding something like a TXT record on the fly, which shouldn't require A/AAAA records.

    So you should be able to do the second type of challenge without a global A record to get a wildcard certificate, and use local DNS for the A record?

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