Inspired by this comment to try to learn what I’m missing.
- Cloudflare proxy
- Reverse Proxy
- Fail2ban
- Docker containers on their own networks
They aren’t on the internet mainly.
My router (opnsense) has a wireguard server which is how I access things when out of the house.
I do have a minecraft server for my friends and I, but that VM is on its own network isolated from everything else.
I expose some stuff through IPv6 only with my Synology NAS (I am CGNATED) and I have always wondered if I still need to use fail2ban in that environment…
My Synology has an auto block feature that from my understanding is essentially fail2ban, what I don’t know is if such a feature works for all my exposed services but Synology’s.
use a cheap vlan switch to make an actual vlan DMZ with the services’ router
use non-root containers everywhere. segment services in different containers
Just tailscale really.
My services are only exposed to the tailscale network, so I don’t have to worry about otger devices on my LAN.
A good VPN with MFA is all you really need if you are the only user.
As many others have said, not allowing inbound WAN connections into my LAN is an important step. I also run k3s on my server with Calico as the CNI and make heavy use of network policies to keep anything I’m running from misbehaving. That, along with easy ingress makes k3s worth it for me over Docker Compose. I use OpenWRT on my router and force certain devices to run through a VPN and block other devices from the internet entirely.
Tailscale and being at my house is the only two ways in so I feel those are pretty good for me.
To add some points, that I do:
- Proper logging: So I could realize something unusual is going on
- rootless podman container: harder to escalate privileges and gain root
- Apparmor: same, plus it could trigger suspicious log entries
- Fail2ban
- UFW
- Reverse Proxy
- IPtraf (monitor)
- Lynis (Audit)
- OpenVas (Audit)
- Nessus (Audit)
- Non standard SSH port
- CrowdSec + Appsec
- No root logins
- SSH keys
- Tailscale
- RKHunter
If I need remote access, I just log into NPM and I have certain URL’s created for Plex, or Sonarr, Radarr etc. No issues so far.
Default block for incoming traffic is always a good starting point.
I’m personally using crowdsec to good results, but still need to add some more to it as I keep seeing failed attacks that should be blocked much quicker.Some I haven’t yet found in this thread:
- rootless podman
- container port mapping to localhost (e.g.
127.0.0.1:8080:8080) - systemd services with many of its sandboxing features (PrivateTmp, …)
I assume #2 is just to keep containers/stacks able to talk to each other without piercing the firewall for ports that aren’t to be exposed to the outside? It wouldn’t prevent anything if one of the containers on that host were compromised, afaik.
It’s mostly to allow the reverse proxy on localhost to connect to the container/service, while blocking all other hosts/IPs.
This is especially important when using docker as it messes with iptables and can circumvent firewall like e.g. ufw.
You’re right that it doesn’t increase security on case of a compromised container. It’s just about outside connections.
OK, yah, that’s what I was getting at.
Containers can talk to each other without any ports exposed at all, they just need to be added to the same docker network.
I was getting more at stacks on a host talking, ie: you have a postgres stack with PG and Pgadmin, but want to use it with other stacks or k8s swarm, without exposing the pg port outside the machine. You are controlling other containers from interacting except on the allowed ports, and keeping those port from being available off the host.
You can do that by joining the containers to the same docker network, you don’t need to expose ports even to localhost.
Does adding 127.0.0.1 make it so only that server can access it or what? I’ve seen that but not understand
Yes. 127.0.0.0 is the localhost. This is the IP the container is listening on. Even if there was no firewall it wouldn’t allow any connection except from the host. If it’s set to 0.0.0.0 it means it’ll allow connections from any IP (which might not be an issue depending on your setup).
The reverse proxy runs on localhost anyway, so any other IPs have no reason to ever have access.
Yes. 127.0.0.0 is the localhost. This is the IP the container is listening on. Even if there was no firewall it wouldn’t allow any connection except from the host. If it’s set to 0.0.0.0 it means it’ll allow connections from any IP (which might not be an issue depending on your setup).
Thanks for explaining this!
One thing I do is instead of having an open SSH port, I have an OpenVPN server that I’ll connect to, then SSH to the host from within the network. Then, if someone hacks into the network, they still won’t have SSH access.
I do the same, but with Wireguard instead of OpenVPN. The performance is much better in my experience and it sucks less battery life.
I’ve been meaning to learn how to make my own
I found the guide/examples on their website a bit irritating at first (that’s on me) but it works well once understood and configured.
Fail2ban config can get fairly involved in my experience. I’m probably not doing it the right way, as I wrote a bunch of web server ban rules — anyone trying to access wpadmin gets banned, for instance (I don’t use WordPress, and if I did, it wouldn’t be accessible from my public facing reverse proxy).
I just skimmed my nginx logs and looked for anything funky and put that in a ban rule, basically.
Thanks!
Here’s the setup I followed. It seems like it might take away some manual work for you: https://m.youtube.com/watch?v=Ha8NIAOsNvo&t=1294s&pp=ygUIRmFpbDJiYW4%3D
I put up a sign that says, “No hackers allowed plz”
How has that been going?
“All your containers are belong to us.”
I don’t put it on the Internet.
I have automatic updates enabled and once in a while I scan with Nessus. Also I have backups. Stuff dying or me breaking it is a much greater risk than getting hacked.
I agree - I don’t expose anything to the internet other than the WireGuard endpoint.
I’m only hosting services that my immediate family need to access, so I just set up WireGuard on their devices, and only expose the services on the LAN.
I used to expose services to the internet, until one of my #saltstack clients was exploited through a very recent vulnerability I hadn’t yet patched (only a week or so since it was announced). I was fortunate that the exploit failed due to the server running FreeBSD, so the crontab entry to download the next mailicious payload failed because wget wasn’t available on the server.
That’s when I realised - minimise the attack surface - if you’re not hosting services for anyone in the world to access, don’t expose them to everyone in the world to exploit.
I don’t expose anything to the internet other than the WireGuard endpoint.
This is the way
TBF if you want, you can have a bastion server which is solely whitelisted by IP to stream your content from your local server. It’s obviously a pivot point for hackers, but it’s the level of effort that 99% of hackers would ignore unless they really wanted to target you. And if you’re that high value of a target, you probably shouldn’t be opening any ports on your network, which brings us back to your original solution.
I, too, don’t expose things to the public because I cannot afford the more safe/obfuscated solutions. But I do think there are reasonable measures that can be taken to expose your content to a wider audience if you wanted.
Is Nessus free for personal use?
For up to 16 endpoints or something like that, yes.
