I want to make Linux my main OS. I’ve used Windows for decades. Since Vista or 7, the Windows security model is this, from what I understand:

  1. unprivileged programs have limited/no ability to do scary things to your computer. they might be able to read some data, but it’s not going to implant malware in the boot sequence for Windows.
  2. if a program wants escalation, it triggers a UAC popup and the user has to accept it. Remote programs cannot accept UAC on a physical person’s behalf. Escalated programs have admin level control and can do the scary things.
  3. As with any OS, there may be privilege escalation vulnerabilities that escalate (1) into (2).

I’ve only had Windows malware a few times since Win7, and the entry point was fairly avoidable. (Running a sketchy EXE, and a possible drive-by malware install via an advertisement. I could never prove the latter.)

I have never run a password on my Windows machines.

On any system, physical access is game over.

On Linux, the password is paramount. I’ve tried to understand the security model and I keep failing. Synthesizing from arch wiki

SSH

Equivalent to local physical access as the user. If it’s a sudoers or root account, it can do scary things. Not a threat if ssh is disabled or well secured (password or key pairs).

If a network has a well configured firewall (on the router), it should block ssh requests from outside the network unless the admin specifically wants SSH outside the network.

As with any OS, there may be bugs that allow remote access outside of SSH.

Local login / password prompts to physical users

Without a password, you can’t escalate to root and install new software. Some software, often dealing with hardware (smartctl) requires sudo/root to run.

Encrypted drives

Passwords can decrypt drives if they are encrypted.

Keyrings

Some DEs (KDE) offer a ‘keyring’ that stores passwords. It’s locked/encrypted with a password, usually the same as the login password.

So what am I missing? Is Windows + UAC + no password secure? What is Linux protecting us from by using passwords?

  • Trying2KnowMyself [they/them, comrade/them]@hexbear.netEnglish
    6·
    5 hours ago

    I don’t use Windows often, so I might be missing some context - every Windows computer I’ve used has an account with a password that I need to type in sometimes, though admittedly not for every privileged operation. They prevent most people with physical access from doing anything, in the same way that the locks on your doors or windows do. Opportunistic actors are prevented from access.

    Most Linux distros probably tend to prompt you to actually type in your password more often, but:

    • SSH: if you aren’t connecting to your computer via SSH you have no reason to be running an SSH Server. In most cases, you should be using a key pair for auth, and the password for the key (if set) is what you’re typing in. This provides a layer of security beyond what a password-less key pair offers because physical access to your private key no longer grants access to the remote system without the password.
    • Encrypted drives: similarly adds a layer on top of physical access necessary to decrypt the data
    • Keyrings: password re-use is a bad thing, and re-using your login password for what amounts to a password manager is also not great practice, though admittedly relatively common