These servers I had an account setup too were, from what I observed, partially linked with the authentication mechanism used by the VPN and IAM services. Like they'd have this mandatory password reset process and sometimes sudo was set to that new password, other times it was whatever was the old one. Couple that with the high latency connection and password authentication was horrible. You would never know if you mistyped something, or the password itself was incorrect or the password you pasted went through or got double pasted.
I think this is a great addition, but only if it leads to redhat adopting it which is what they were running on their VMs.
But yeh, never thought this was a problem anyone else delt with. My passwords are all a variant of my on "master password" and sometimes forget which session I'm in so trying to save keystrokes, count backward to where I think the cursor should be.
One thing people are really, really good at is detecting others near them, because it was essential for not getting eaten back in the day. So the chances of (a) someone wanting to shoulder-surf (b) being close enough to do so and (c) getting away with it are essentially zero. It was a security measure that made sense in 1973 when you were on a model 33 leaving a printed record in a machine room with a dozen other people, but has been completely nonsensical for several decades.
Which is probably why it invokes so much irrational religious fervor.
But you should not type sudo passwords on remote machine. Instead setup your machinr to have nopassword for special sdmin account and enable pubkey only authentication.
I personally use the pam ssh agent module for this, that way you can use agent forwarding with sudo.
In any case, I don't understand the issue. TCP is "reliable" so it's not like you'll get dropped keystrokes. Just type the password and hit enter, and the entire string will go through when it goes through
i feel this in my bones.
does anybody know what level this change happens on? is this change going to affect ubuntu desktop users on any system they ssh into, or will it affect all users of a ubuntu server who have ssh'd in?
If you are on a high latency ssh connection and your password does not register, you most likely mistyped it.
The passwords get updated irregularly with the org IAM so you aren't sure what the password even is. Pasting doesn't work reliably sometimes, if you're on windows you need to right click to paste in terminals, sometimes a shortcut works. Neither gives me any feedback as to what event was ever registered though.
In the modern world there is no plausible scenario where this would compromise a password that wouldn't otherwise also be compromised with equivalent effort.
Only if length is known. Which is true now. So it opens the gates to try passwords of specific known length.
Or, we could just look at the keyboard as they type and gain a lot more information.
In an absolute sense not showing anything is safer. But it never really matters and just acts as a paper cut for all.
Have you ever watched a fast touch typist, someone that does over 100 words per minute? Someone who might be using an keyboard layout that you're not familiar with? When the full password is entered in less than a second it can be very difficult to discern what they typed unless you're actually recording with video.
But sure, if you're watching someone who types with one finger. Yes, I can see that.
In the early days we all shared computers. People would often stand behind you waiting to use it. It might even not have a screen, just a teletype, so there would be a hard copy of everything you entered. We probably didn't have account lockout controls either. Knowing the length of a password (which did not tend to be long) could be a critical bit of info to reduce a brute force attack.
Nowadays, not so much I think. And if you are paranoid about it, you can still set it back to the silent behaviour.
Not sure about that. I'm no expert but for high risk scenarios one might have to worry about binoculars from the building opposite your window, power line monitoring, and timing attacks. All scenarios where the attacker cannot see your hands/keyboard.
Combine that with a flaky keyboard (say from a single grain of dust where it shouldn’t be) and you get a very annoying login experience. Over and over…
If you have Capslock set to change your keyboard language, and your computer locks with Capslock enabled, you literally can't type lowercase letters of your password. Capslock doesn't work, shift doesn't make it go lowercase - you literally just have to reboot to get back in.
How would your computer lock with capslock enabled? I.e. if capslock on that computer is set to change keyboard language?
I use Open Core Legacy Patcher (OCLP) to run modern macOS on old Intel macs. The first time the computer boots after an upgrade (e.g. Sequoia 15.7.3 to 15.7.4), it is slow as a dog. Because the macOS upgrade clobbers all the OCLP driver patches.
By "slow", I mean each keystroke on the login screen takes about 20-30 seconds for the corresponding bullet to appear in the password box.
The login screen displays 13 bullets. My password is 18 characters long. (Scammers, don't get excited, it's a unique password that's not used anywhere else on the Internet...) So after 13 characters, I had no idea if the computer was actually working.
It seemed like there is a 6-8 character keyboard buffer limit. Or maybe I typed in my 18-character password wrong multiple times. I don't know. I would type 2 characters, then walk away, come back, then type 2-3 more characters. It took me about 4-5 attempts over 30 minutes to log in. Then I applied the OCLP patches and everything worked perfectly after that.
I was much too young to use it myself, but I saw other people log in and it was amazing.
The glyphs denoting hidden password characters changed on every keystroke to indicate you were typing. And IIRC, they were cool characters like Egyptian hieroglyphs too. (Presumably this wasn't some hash of your actual password - that would actually be dumb. I do think it indicated password length, which could give away info, but it's also useful for the user.)
Edit: this is not exactly as I remember, but it might be the same system: https://security.stackexchange.com/questions/41247/changing-...
If that's how it was implemented, then that's not great.
IIRC, originally it echoed one glyph per character typed, but later it definitely echoed 1 to 3 glyphs at random so it wouldn't leak your password length.
The password thing was pretty cool, but it's literally the only good thing about Lotus Notes, which was the most archaic and primitive piece of commercial GUI software I've ever used in 45 years of software experience. I last used it in 2003, and even then its UI was so archaic, it didn't adhere to behaviors (like keybindings, and other basic UI elements) that had been standard since the 80s.
Absolute garbage software.
Whimsy, and character.
Used to be that everything was trying to look different. Now it seems like everything is trying to look the same.
----
For KDE:
sudo vim /etc/sddm.conf.d/hide-password.conf
[Greeter]
ShowPasswordEcho=false
----
For `sudo`:
sudo vim /etc/sudoers.d/password-no-visual-echo
Defaults !pwfeedback
For GNOME, you have to modify `unlockDialog.js`
sudo vim /usr/share/gnome-shell/js/ui/unlockDialog.js
this._passwordEntry.clutter_text.set_password_char('');
The default entry on xsecurelock[^0] shows a character jumping on a line between keystrokes, which works well on giving key press feedback while visibly obfuscating password length,
________|_______________________ // after pressing a key it'd move around,
___________________|____________
# /etc/sudoers
Defaults !pwfeedback
security.sudo-rs.extraConfig = ''
# NixOS extraConfig
# ===========
Defaults !pwfeedback
'';
On some systems I've gone as far as removing that delay. It's either that, reusing the same password everywhere, or losing my fucking mind. This should fix that wonderfully.
That said, with any feedback that confirms my key was pressed I can pretty much always correct a mistake using backspace without trouble (with backspace also having visual feedback).
It might matter a bit more for dictionary-based attacks (you don't have to bother hashing dictionary permutations that don't match the expected length) but I still suspect it doesn't save you much.
It doesn't make sense to show the exact amount of characters. It just leaks the password length.
I thought that was kinda clever; it gives you feedback when your keystrokes are recognized, but it's just enough confusion to keep a shoulder surfer from easily being able to tell the length of your password unless you're hunt-and-pecking every single letter.
Of course, once you do understand that it's just a password prompt, it's great. Completely confuses the hell out of any shoulder surfers, who will for sure think it's a confusing puzzle, and eventually they will get rate limited.
^1: Example of it in use: https://www.youtube.com/watch?v=FvT44BSp3Uc
> That way you can be certain whether or not you entered a character
What's the benefit of having a random character from a random set, instead of just a random character?
"That way you can be certain..." absolutely not.
Presumably they’re capable of buying a $5 wrench to physically use against you.
Alternatively, if it's confusing, you shouldn't be doing whatever it is you're doing with sudo because you copy pasted a command from God knows where with zero understanding.
I think it's an awful idea. Apart from making things less secure it also makes sudo's UX inconsistent with most of the other coreutils. Luckily, I don't plan on doing any more ubuntu installs.
As for security: 'shoulder surfing' may not be as much of a concern, but watching a livestream or presentation of someone who uses sudo will now expose the password length over the internet (and it's recorded for posterity, so all the hackers can find it later!). They've just introduced a new vulnerability to the remote world.
Besides, I can just amplify their stream to hear their keypresses.
You actually believe that every person in the world who shares their screen is aware of computer security best practices? Or are we only limiting this generalization to every one of the millions of YouTube/Twitch livestreamers?
> I can just amplify their stream to hear their keypresses.
Maybe if they have Cherry MX Blues? A normal keyboard would not get picked up by modern apps' recording noise suppression (the filters are designed to eliminate the sound rather than merely lower volume).
It helps 99% of the user base and the security risk seems negligible.
Also, I think the vulnerability of knowing that someone's password is exactly 19 characters long is low enough to be worth the tradeoff. Especially since someone on a livestream can also figure that out by listening for the keypresses.
Changing the default is the point, because people often just don't look into whether it's possible to configure things. They might not even get the idea that the asterisk feedback could be possible, or useful, until it's shown to them.
In your specific example livestreams usually have audio so the length is already public.
Also what demos are you doing that require sudo access to your local machine? That’s already pretty niche.
I would've thought it would've been a simple carry over from before terminals were glass. Like, yeah, I get up from a glass terminal and someone else goes to use it, but wouldn't the scrollback be cleared when I log out? But silent logins from before glass terminals makes a ton of sense; it would literally print your typed characters on a real, physical medium. having
login: cool_user
password: hunter2
I dunno, I take them at their word but if you had asked me why password prompts in the terminal don't echo, I would've guessed it was a carry-over from the days of real teletype terminals.
I suppose you could do character buffering and quickly change to normal, print an asterisk, and back to silent mode in one write. But likely there's always some kind of edge case where things work differently. It's not difficult to disable so this may be better for the 99% and the 1% can change it back.
It's on brand for Ubuntu, though. They've been looking for an audience that is not me for a very long time. I sometimes worry about Debian's resistance to social pressure, though. It seems that Debian doesn't fall for marketing or corporate pressure, but they sometimes fall when they are surrounded by people who have fallen for marketing or corporate pressure.
The correct change would be leave the default and put in the visudo file for easy uncommenting. The "developers opinion" is flat wrong.
# uncomment below to see *s when typing passwords # Defaults pwfeedback
All of the dev thinking on the matter is based on narrow use-cased "if you're on a a host where login to a login screen and people can see you... "
When users connect via ssh keys to production hosts and type sudo passwords, I do not one iota of potential security benefit lost.
- If it's so short that the knowledge of the length makes bruteforcing noticeably faster, the password is so short that the total length taken would be very short regardless.
- In all other cases, it removes such a small fraction of time needed (on the scale of removing one age-of-the-universe from a process that would otherwise take thousands of ages-of-the-universe) that it doesn't change any infeasible timescale to a feasible one.
So either the information isn't needed, or it won't help. So not a security decrease.
If we know the password's length, it saves us from guessing any shorter passwords. For example, for a numeric password, knowing the length is 4 saves us from having to guess [blank], 0-9, 00-99 and 000-999. This lowers the number of possibilities from 1111 to 1000. The password has 90% of it's original strength. A [0-9a-zA-Z] password retains 98% of it's original strength
The set of all strings, of any length over A, is an infinite set, because it is the union of all sets of strings of length n for each positive integer n.
So if you don't know the length of the password, there are infinite possibilities. If you do know the length of the password, there are only finite possibilities.
Which would in turn imply that there is an infinite amount of information in knowing the length of a password - the complement of the set of n-length strings over A in the set of strings over A contains an infinite number of elements, which you can safely exclude now that you know the password is part of the finite set of n-length strings over A.
Your argument therefore doesn't apply in this context.
This wasn't someone seeing Chesterton's fence and deciding to knock it down thoughtlessly. This is a change that someone can in fact think all the way through and say "yeah, this should be changed, it's an improvement and doesn't cause any meaningful reduction in security".
`sudo` and `login` are I think the only two tools I use that don’t provide any feedback.
Otherwise my entire life is behind a password database that lets me see my password in plaintext and otherwise shows the length of it as it’s typed. KeepassXC.
If knowing how the length of your password makes it easy to crack you probably have other problems
Knowing the length narrows down the search space some, but a meaningfully long password basically makes that knowledge useless, and again, it’s only useful if the approach they take is to try to physically possess your computer or obtain an encrypted backup.
A far more likely effort is going to be a spear fishing email, especially since if they have physical access to you they probably know a lot about you, and what services to spoof to get you to give them passwords, and so on.
Conversely, making people more comfortable with security measures may well improve security; for instance, some people will have an easier time typing in longer and more complex passwords thanks to password feedback.
Usability is often a security feature.
I didn't actually know that Mint had enabled this by default. That would have been a useful counterpoint to the naysayers.
If you want the original behaviour you don't actually need to change the configuration - they added a patch afterwards so you can press tab and it will hide the password just for that time.
> The catalyst for Ubuntu’s change is sudo-rs
Actually it was me getting sufficiently pissed off at the 2 second delay for invalid passwords in sudo (actually PAM's fault). There's no reason for it (if you think there is look up unix_chkpwd). I tried to fix it but the PAM people have this strange idea that people like the delay. So I gave up on that and thought I may as well try fixing this other UX facepalm too. I doubt it would have happened with the original sudo (and they said as much) so it did require sudo-rs to exist.
I think this is one of the benefits of rewriting coreutils and so on in Rust - people are way more open to fixing long-standing issues. You don't get the whole "why are you overturning 46 years of tradition??" nonsense.
If anyone wants to rewrite PAM in Rust... :-D
If you do, offer support for writing modules in a scripting language like Lua or Python. PAM could make it a lot easier to just add OAuth with your company IdP, for example…
(compare: polkit. Both sides have their point, but I've been annoyed by this standoff a few times).
Respectfully, we are the opposing sides of the barricades here. I was removing sudo-rs, uutils and some of the systemd-* packages from fresh Ubuntu installations until the amount of virtue signaling got really tiresome.
Currently almost no Ubuntu left in my production. Hopefully Debian will not package those.
PS: Rust is awesome!
The reason is to add a delay when bruteforcing passwords.
https://github.com/pibara/pam_unix/blob/master/unix_chkpwd.c...
I doubt this is a super common threat but I would expect it to be already applied by spies or "Jia Tan" like employees.
Did you wind up sticking with Windows (or Mac) for a long time after this? How long until you tried again?
I value ctrl+U a lot more for password prompts than the visual feedback, it's even used by GUI on Linux.
apt install sudo-ws
apt remove coreutils-from-uutils --allow-remove-essential
However it is pretty obvious at this point that Ubuntu will absolutely remove those from one of the future releases because availability of real sudo and coreutils is detrimental to the virtue signaling they are engaging in.
After being a lifetime Ubuntu user I have moved to Debian across almost all of my production.
Uniqueness is the number one thing that matters. The modal attack is a remote credential stuffing attack by someone trying millions of email/password combinations from a database.
Not showing feedback on user input is objectively confusing for inexperienced users.
And yes, it remember how many it echoes so backspace works correctly.
> For a time, there was rich pickings in applications that accepted passwords in unbuffered mode. Many of them doing it so that they could echo "*" symbols, character by character, as the user typed. That simple feature looks cool, and does give the user feedback ... but would leak the keystroke rate, which is the last thing you want on password entry.
This was in response to keystroke timing defense on SSH. Does this feature still come with the risk of leaking keystroke timing to an attacker with recent OpenSSH/Dropbear versions? If so, it might be wise to keep it disabled on servers.
> Specifies whether ssh(1) should try to obscure inter-keystroke timings from passive observers of network traffic. If enabled, then for interactive sessions, ssh(1) will send keystrokes at fixed intervals of a few tens of milliseconds and will send fake keystroke packets for some time after typing ceases. The argument to this keyword must be yes, no or an interval specifier of the form interval:milliseconds (e.g. interval:80 for 80 milliseconds). The default is to obscure keystrokes using a 20ms packet interval. Note that smaller intervals will result in higher fake keystroke packet rates.
Although that's on the client-side, if the server responds with a "*" symbol for each keystroke it might be possible to reconstruct password length from network traffic.
To reduce the length exposure, the software could randomly show multiple asterisks per key-stroke. I think Lotus Notes did this. Of course, this may lead to people suspecting keybounce.
I've successfully shoulder-surfed someone to discover their password (in response to a sudo prompt) by watching their hands and fingers. So if the person is close enough, having echoed stars or not makes no difference. It was long password too, but contained two whole lowercase words.
A space with a cursor instead of an asterisk would make it harder to count the Chars
Adding a random 1 to 3 output chars instead of one would obfuscate this even more.
A delayed output could make you submit the password prompt before showing anything.
A single asterisk that switches back to space after 250ms inactivity may even be better.
I don't know, but somehow this feels underthought even if it probably is not. Simple is probably the best approach
Users expect to see exactly 1 new char (either the key pressed or an asterix) when they type something. Seeing up to three chars appearing or disappearing after some time imho is worse than what we have today.
Reverse the logic and make a “sudo_h” script which hides the password entry for those rare times you need it.
Though I guess the broader context is if the attacker has "shoulder-level access" you probably have bigger things to worry about ;)
The other side of that coin: If you see a password prompt on someone's screen, turn your back.
Seriously, what does sudo even protect anymore, and when are you typing it with someone looking over your shoulder?
If you have a Linux or Mac desktop, the login password prompt has the same design choice regarding showing characters and is much more likely to actually be used in front of someone. In modern Linux development, you shouldn’t be using sudo most of the time, and on ssh machines, you shouldn’t have a sudo password.
And even if someone did see it then they’d have to get physical access to your machine. If someone has easy physical access to your machine and wishes you harm, then knowing the length of your desktop login is probably the least of your worries.
It feels like dumbing down the cli.
But I don't know if this is an elder millenial walk up hill in the snow both ways kind of thing though.
Am I alone in this?
Edit: and the article clearly states, incorrectly, "That behaviour survived — untouched — through nearly half a century of Linux distributions."
Is it usable now? Do all utilities support all of GNU's features (or most)?
There is a list of open items here, it's looking pretty good tbh: https://github.com/orgs/uutils/projects/1
I'm sure someone things this is a good idea, but I do not, and nobody cares what I think. But I come from being a long-time coder who's always been a terrible typist and can't depend on "touch typing" and have to actually look at things, like the keys, and the screen. And handicapped by going blind in one eye, and having arguments with eye doctors who say "get used to it and switch to audio books" and needing 14-point boldface fonts for everything.
So hide the first one as well? But also, that's not true, not all terminal passwords are for local machine
> Confusing — appears frozen
So make it appear flashing? Still doesn't need to reveal length
The expectation with sudo is silent passwords.
How about all the daemons that double log or double timestamp on systemd machines?
The crazier part is Ubuntu using a pre-1.0 software suite instead of software that has been around for decades. The switch to Rust coreutils is far too early.
I always thought it was annoying anyway.
I don't really want to just disable passwords. I recall that causing technical pains. And this is a desktop PC in my home office and I'm just generally okay with the associated security risks.
You could probably throw together a quick PAM module that scans for your phone's presence. But, aside from the security/spoofing risks, Bluetooth scanning can take half a minute even when you have the device set to be discoverable so you may be faster off typing in your password.
Alternatively, you could just disable the password prompt for sudo if you make sure to always lock your screen. Or not even that if you don't have disk encryption enabled, as anyone with malicious intent can do anything to an unencrypted laptop anyway.
Truly, when anything in Slashdot News (delete delete) "HaCk3R Newz" has more than about 300 comments, I know it will be a merry-go-round of imbeciles regurgitating nonsense. A moronic choir of nobodies singing the same note. This one didn't disappoint.
Instead of doing this, Ubuntu is just using a Rust rewrite of sudo. Some things really never change.
Without knowing more, creating a transient unit just to run a single shell command seems quite roundabout.
You'd think by now they'd have learned, but apparently not.
What?!
2026 minus 46 is 1980. There was no Linux, at all, in 1980.
Someone is quite confused.
The security argument is a red herring. It was originally built with no echo because it was easier to turn echo on and off than to echo asterisks. Not for security.
Because to hell with UX when it comes to security. Knowing the exact length of a password absolutely makes it significantly less secure, and knowing the timing of the keystrokes doubly so.
One implies the other. You turn echo off. Then you write asterisks.
> Not for security.
Consider the case of copy and pasting parts of your terminal to build instructions or to share something like a bug report. Or screen sharing in general. You are then leaking the length of your password. This isn't necessarily disastrous for most use cases but it is a negative security attribute.
⣾, ⣽, ⣻, ⢿, ⡿, ⣟, ⣯, ⣷
This reminds me. Linux was already a fossil, except for some niches, but now in the age of AI, the fact that code can't be updated at will (and instead has to go through some medieval social process) is fatal. Soon the age will be here where we generate the necessary OS features on the fly. No more compatibility layers, no more endless abstractions, no more binaries to distribute, no more copyright, no need to worry about how "the others" use their systems, no more bike shedding. Instead, let the system manage itself, it knows best. We'll get endless customization without the ballast.
It's time to set software free from the social enclosures we built around it.
