You seriously need to stop what you’re doing. Log in with ssh only. If you need multiple terminals use multiple ssh sessions, or screen/tmux. If you need to search something do it on your desktop system.

The server should not have Firefox installed, or KDE, or anything related to desktop apps. There’s no point and nothing good can come of it.

I think there are many security issues with your setup. You really, really shouldn’t do everything as root. That is just a time bomb waiting to blow.

Your frame of mind is “dangerous”. If you are browsing on your servers as root, you need to not manage servers anymore. If that sounded harsh, learn about attack surface area first and then I might let you back in the server room.

You won’t find discussions about running browsers as root because it’s not something you should need to discuss. Also, you don’t need to be browsing “shady” websites to get compromised. Get that myth out of your head.

find it more convenient to use the command line from a remote desktop instead of directly SSH-ing into the system

How is extra steps and added latency more convenient? The latency of a console via remote desktop would drive me crazy. Hell, I haven’t installed any kind of desktop environment on Linux server for over 20 years. It’s not needed and a waste of resources. Who needs file managers anyway?

Is it actually dangerous to run Firefox as root?

Yes, very. This is not specific to Firefox, but anything running as root gets access to everything. Only one thing has to go wrong for the whole system to get busted.

usually logged into KDE Plasma as root.

Please don’t do this! DEs are not tested to be run as root! Millions of lines of code are expected to not have access to anything they shouldn’t have and as such might be built to fail quietly if accessing something they shouldn’t in the first place. Same thing applies to Firefox, really.

I have no clue how dangerous running Firefox as root is, but it begs the question…why would you do that?

Create a user account for managing things and create a separate user for each service and/or containers.

For managing things use tmux with ssh, if you want to manage files etc. just use ranger/lf/mc. One can also mount the file system with sshfs.

Yes, it is. As a user you compromise only that user as a consequence of some sandbox escape. Then there may or may not be some successful privilege elevation.

but no one seems to be discussing how risky it actually is.

That is because people stopped doing it ages ago.

But shouldn’t Firefox be sandboxing every website and not allowing anything to access the base system?

Security is always a matter of layers. Any given layer can fail some of the time but you want to set up your security so situations where all the layers fail together are rare.

My goodness

It’s about as dangerous as using IE in the old days, or Edge in administrator mode.

This is like removing a safety feature in your car. Like removing seatbelts or maybe anti-lock brakes.

Realistically it’s not super dangerous, and no you probably don’t have a virus just from browsing a few tech support sites, but you do eliminate your last line of defense when you run software as root. As you know, root can read/change/delete anything on your system whereas regular users are generally restricted to their own data. So if there is a security problem in the software, it’s made worse by the fact that you were running it as root.

You are right though that Firefox does still have its own protections - it’s probably one of the most hardened pieces of software on your computer exactly because it connects to the whole wide internet - and those protections are not negated by running as root. However if those protections fail, the attacker has the keys to the kingdom rather than just a sizable chunk of the kingdom.

To put that in perspective though, if there is a Firefox exploit and a hacker gets access to your regular user account, that’s already pretty bad in itself. Even if you run as a regular unprivileged user they would still have have access to things like: your personal documents, your ssh keys, your Firefox profile with your browsing history, your session cookies and your saved passwords, your e-mail, your paypal account, your banking information, …

As root, they could obviously do even more like damage like reading all users’ data, installing a keylogger or screengrabber, installing a rootkit to make themselves undetectable, but for most regular users most of the damage is already done when their own account is compromised.

So when these discussions come up, I always have to think about this XKCD comic:

Usig anything as root is a security risk.

Using any UI application as root is a bigger risk. That’s because every UI toolkit loads plugins and what not from all over the place and runs the code from those plugins (e.g. plugins installed system wide and into random places some environment variables point to). Binary plugins get executed in the context of the application running and can do change every aspect of your program. I wrote a small image plugin to debug an issue once that looked at all widgets in the UI and wrote all the contents of all text fields (even those obfuscated to show only dots in the UI) to disk whenever some image was loads. Plugins in JS or other non-native code are more limited, but UI toolkits tend to have binary plugins.

So if somebody manages to set the some env vars and gets root to run some UI application with those set (e.g. using sudo), then that attacker hit the jackpot. In fact some toolkits will not even bring up any UI when run as root to avoid this.

Running any networked UI application as root is the biggest risk. Those process untrusted data by definition with who knows what set of plugins loaded.

Ideally you run the UI as a normal user and then use sudo to run individual commands as root.

I just wanted to add that you can run gui applications through ssh with x11 forwarding, options -X or -Y (untrusted/trusted but at least in Debian back in the day they behaved the same). So if you wanted a gui file manager you run it in the ssh session on the remote server, sudo if you need but NEVER logged as root, and the window will pop on your local DE instead of having to run an entire desktop on each server

I don’t want to step on your workflow too much since it somehow seems to work for you but your main issue stems from the fact that you clearly don’t work with your server as if it actually was a server.

You shouldn’t really have a desktop interface running there in the first place (let alone as root and then using it as a regular user). You should ask yourself what it actually solves for you and be open to trying different (and more standard) solutions to what you’re trying to achieve.

It’d probably consist of less clicking and using the CLI a bit more, but for stuff like file management you can still easily use mc.

If you need terminal sessions that keep scrollback and don’t stop when you disconnect you should learn to use tmux or screen or something like that. But then again if you’re running actual software in there then you should probably use a service (daemon) for that.

As for whether it’s a security issue, yeah it most definitely is. Just like it’s a security issue to run literally any networked application as root. Security isn’t black and white and there are trade offs to be made but most people wouldn’t consider what you’re doing a reasonable tradeoff.

Without any judgement: why are your servers running X11? Just because you dislike SSH’ing to them?