this post was submitted on 11 Aug 2023
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Wait wtf? You can just reset root password that easy? What’s even the point of having a password, if all of your data and info is so easily accessed if someone gets physical hold of the machine. I guess so software/remote hackers can’t get your stuff, but still. This seems wild to me, I dunno.
New to Linux so I’m sorry if I’m being ignorant, but it does seem crazy you can get access to a machine without the password.
Edit: Thanks for all the comments below! I guess I’ve been spoiled by BitLocker in Windows being enabled by default and not having to think of disk encryption. Appreciate everyone’s time and responses!
There needs to be some mechanism to recover your machine should this happen. It's not that much more difficult to do it on a windows machine either.
The truth of the matter is is if somebody has physical access to your machine it's not your machine anymore. They can pull out the hard drive and plug it into a machine that they have a password for and read from it if it's not encrypted. So on and so forth.
Which is why you never throw away a computer with the drives in it and you never throw drives away without physically destroying them. Don't give other people the chance to see your weird shit.
This is why encryption is important, but physical access to a device will always lead to bad things.
If an attacker has physical access then you're already screwed in most cases.
Pretty much. Even if an attacker can't boot your system, if they have physical access they can just pull your hard drive and mount it on a system they can boot. Only encryption can prevent this. Linux security was originally meant for keeping unprivileged accounts on multiuser systems from messing things up for others on the same machine. It can stretch to some other use cases, but is not a panacea for everything.
And even password based disk encryption can be defeated with 2-3 physical accesses if an organization wants to hard enough. Keyloggers can be very, very sneaky.
At that point you'd have to roll something like Yubikey-based disk encryption to be safe, because this re-establishes control over some physical parts of the system. Until they find the backup Yubikey you had to not lose all data by losing the primary key you're carrying around to maintain control over it.
It's not a battle the defending side can win.
that is unless you're running disk encryption, in which case your data (and in most cases your OS) is safe from unauthorized access, although there is not much to stop them just wiping it or running their own os on it lol
This is always the case, no matter what OS you use, unless you use full-disk encryption. User credentials are all just data on a disk, so if someone has physical access to your machine, and your disk isn't encrypted, then they can access (and change) those credentials or any other data.
See also: https://ostechnix.com/reset-windows-password-with-linux-live-cd/
As you say, preventing remote access is one, but also a password will slow someone down a bit, and stop low-knowledge adversaries entirely, possibly. Also you will at least know someone has messed with your machine if they change the password.
Really, though, there's nothing malicious someone can do to an unencrypted computer by changing the password that they couldn't do without changing the password (copy all your files, delete all your files, install malicious software). Except I guess annoying you by making you change your password back. 😆
Linux can do it to Windows machines too. If it’s not encrypted, USB drive is all it takes.
If it’s not encrypted, a live usb can read all the data on any machine anyway.
I believe it's better not to pretend that an OS password is a secure protection of your data when physically access can just mean - I don't like that OS, I'm going to put on this OS instead, or indeed, I don't like this PC, I'm going to put your data in this PC instead.
Remember, most PCs can become someone else's PC just by plugging in the right USB key. In fact most Linux users will know that, having literally done this themselves.
Yes, there are other ways of doing it as well, you can plug in a live iso and chroot into your proper root and change it for example. This is why you can put a password on GRUB and on your BIOS, even if both of them have passwords, someone can remove your disk plug it into another machine and access your data. Long story short if someone has physical access to your machine is essentially game over. And BTW this is also true for Windows, physical access to the machine has always been considered game over because the person can simply remove the disk and plug it in another system, so any software solution is useless.
This is why encryption is important, if your disk is encrypted putting it in another machine gives garbage unless you know the encryption key, making root rw (as in the link) is useless because you still need to decrypt the disk to access it, plugging a live iso is pointless because unless you know the encryption key you won't be able to chroot into the system. But for most people the fact that no one untrustworthy will ever be physically near your computer is enough to not warrant extra measures of security, not to mention that most people don't have data that could be problematic if leaked (e.g. source code for a large company) and those who do have their drives fully encrypted.
Not exactly true on Windows. BitLocker is enabled by default when signing in with an MS account, which is what I’ve done for nearly a decade and I think is the cause of my confusion. I’m just use to encryption being enabled by default and not having to think about it.
I have NEVER seen personal windows with encryption, I have dual booted and retrieved data from windows computers for everyone else since forever and have never ever seen an encrypted drive. I'm sure some people do encrypt theirs but it's definitely not on by default, same as on Linux where it's one click during the installation that most people don't click.
It’s enabled by default when you login to windows with a Microsoft account, which they very rudely push on you and make it very difficult to login with a regular local account.
Not as far as I know. I've logged in with MS accounts on Windows and still been able to read the disks. Ok Windows 10 and above last one I used was 8.
Just as easy or easier on Windows since it has a GUI. If someone has physical access to your machine your basically screwed. Unless encrypted they could just pop the drive out and put it in another machine also. Also what is more likely for the average user someone comes in and tries to hack your password physically or something gets into your machine and someone tries remotely.
Account passwords have never had the purpose of protecting data from physical access - on Linux or any other operating system that I’m aware of. Physical access means an attacker can pull your drive and plug it into their computer, and no operating system can do anything to block access in that scenario, because the os on disk is not running.
You need disk encryption to protect your data. The trade off is that if you forget the encryption password, your data is unrecoverable by you. But that’s what password managers are for (or just writing it down and putting it in a safe).
I quess if you really want to secure your device you shloud use encryption to encrypt your data and/or make something that wipes all your data in case someone tries to log into your device but that's only when you have something really important to hide.
If somebody had physical access to a machine, they can get into it. If you want your data secured l, use encryption as others have suggested.
Unix was originally a networked system that many terminals would connect to. Being able to actually reach the machine meant that you had authority.
It's the same today. If someone has physical access, the system is so screwed that you can just give total privileges anyways.