42
Do I Need to Harden SSH over Tor? (infosec.pub)
submitted 2 years ago by anon2963@infosec.pub to c/selfhosted@lemmy.world
26 comments fedilink hide all child comments

cross-posted from: https://infosec.pub/post/10908807

TLDR:

If I use SSH as a Tor hidden service and do not share the public hostname of that service, do I need any more hardening?

Full Post:

I am planning to setup a clearnet service on a server where my normal "in bound" management will be over SSH tunneled through Wireguard. I also want "out of bound" management in case the incoming ports I am using get blocked and I cannot access my Wireguard tunnel. This is selfhosted on a home network.

I was thinking that I could have an SSH bastion host as a virtual machine, which will expose SSH as a a hidden service. I would SSH into this VM over Tor and then proxy SSH into the host OS from there. As I would only be using this rarely as a backup connection, I do not care about speed or convenience of connecting to it, only that it is always available and secure. Also, I would treat the public hostname like any other secret, as only I need access to it.

Other than setting up secure configs for SSH and Tor themselves, is it worth doing other hardening like running Wireguard over Tor? I know that extra layers of security can't hurt, but I want this backup connection to be as reliable as possible so I want to avoid unneeded complexity.

you are viewing a single comment's thread
view the rest of the comments
[-] marcos@lemmy.world 21 points 2 years ago

This is the internet. If you poke the bear, somebody will come-up with a completely reasonable use case of password authentication that happened once somewhere on the world.

[-] thebardingreen@lemmy.starlightkel.xyz 3 points 2 years ago

Easy. I have servers that are only available on my local network and lots of different devices that I MIGHT want to use to access those servers. I haven't bothered to make sure my key is on EVERY SINGLE DEVICE and some of them, I might not actually even WANT my key on as they're not terribly well secured and they might leave my house (my Windows gaming laptop I haven't used in six months comes to mind).

But for cloud accessible servers... yeah.

[-] EarMaster@lemmy.world 2 points 2 years ago

You know you're allowed (some might even say supposed) to have different keys for different machines. They're basically free to generate and take up to no space.

[-] captain_aggravated@sh.itjust.works 2 points 2 years ago

Playing with a Raspberry Pi inside my own home network with nothing important going on and I turned the Pi off when I'm done. Like why worry about it at that point?

[-] Acters@lemmy.world 3 points 2 years ago* (last edited 2 years ago)

Yes, but I usually add my public key to the authorized_keys file and turn off password authentication once i do login with a password. On top of that, I have a sshpass one line command that takes care of this for me. It's much easier than trying to manually type a password for the next time. I save it and just run it every time I think about using password login. Next time I need to ssh, I know the password login is not necessary.

sshpass -p 'PASSWORD' ssh USER@IP.ADDRESS "echo '`cat ~/.ssh/id_rsa.pub`' > ~/.ssh/authorized_keys && echo 'Match User !root
PasswordAuthentication no
Match all' > /etc/ssh/sshd_config' && exit" && ssh USER@IP.ADDRESS

At the next reboot, your system will now only accept key logins, except for root. I hope the root user password is secure. I don't require it for root because if a hacker does gain shell access, a password(or priv esc exploit) is all they need to gain root shell. It is also a safety net in case you need to login and lost your private key.

[-] marcos@lemmy.world 1 points 2 years ago

Yeah, that's not a good reason.

It's much easier to authorize a key than to input your password on every kind of interaction.

[-] AbidanYre@lemmy.world 0 points 2 years ago* (last edited 2 years ago)

If there is, I'd love to hear it. But even JuiceSSH on Android has supported keys for like the last decade.

this post was submitted on 10 Apr 2024
42 points (93.8% liked)

Selfhosted

62801 readers
1065 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

  1. Be civil.

  2. No spam.

  3. Posts are to be related to self-hosting.

  4. Don't duplicate the full text of your blog or readme if you're providing a link.

  5. Submission headline should match the article title.

  6. No trolling.

  7. 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. Tags [CBH] or [AIP] are required, see the links in Rule 8 for details.

  8. AI-related discussions and AI-involved promotional posts have additional requirements for tagging, as noted in Rule 7 and the AI & Promotional Post Expanded Rules post, and find example disclosures here.

Resources:

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

Questions? DM the mods!

founded 3 years ago
MODERATORS
ruud@lemmy.world
Loki@lemmy.world
CannaVet@lemmy.world
devve@lemmy.world
ayyy@sh.itjust.works
curbstickle@anarchist.nexus
curbstickle_lw@lemmy.world