Linux user login no password

How to create a user without password in Linux

This article title may sound awkward to you, but it’s useful. You may ask, why would we want to create a user without a password. I thought that too, but my friend faced this question in one of the interviews.

So, I want to share this with users who are looking for an answer to this question. Practically it may not be useful, but you should know the answer.

This article shows you how to create a user account without a password OR an empty password on Linux.

What is passwd command?

The passwd command is one of the most frequently used command by Linux administrator’s to update users’ authentication tokens in the /etc/shadow file by calling the Linux-PAM and Libuser API’s.

What is useradd command?

Linux is a multi-user operating system that allows more than one user to interact with the system at the same time. The “useradd” command is used to create new user accounts. When executed, “useradd” command creates a new user account as per the options specified in the ‘/etc/default/useradd file’ & ‘/etc/login.defs’ file.

Now let’s delve into some of the methods used to create a user account without password:

Method-1: Creating a user without password using passwd command

You can create a user without a password on Linux using the “passwd” command as follows :

Run the useradd command to create a user account as shown in the example below.

Note: we can use the commands “useradd” or “adduser” interchangeably to create a user in Linux.

useradd is native binary compiled with the system. But, adduser is a perl script which uses useradd binary in back-end. adduser is more user friendly and interactive than its back-end useradd. There’s no difference in features provided.

Once you have created the user, use the passwd command to remove the user’s password.

# passwd -f -u mageshm Unlocking password for user mageshm. passwd: Success

• -f or —force Force operation
• -u or —unlock Unlock the password for the named account (root only)

Method-1.a: Using passwd comamnd

Alternatively, you can use the -d option with the passwd command to remove the password for a user.

# passwd -d magi Removing password for user magi. passwd: Success

Now, you’ve created a user with “disabled password”. But when you try to access it, it will ask for the password at the same time not allowing you to login.

You might get an error message saying “Access denied”.

That’s the expected behavior and you will not receive an error message such as “No password, you cannot login”.

Method-2: Creating a user without password using chpasswd command

You can create a user with an empty password on Linux using the “chpasswd” command.

Run the below command to create a user account:

Once you have created the user, use the below command to remove the user’s password. The -e option expects a hashed password, but you are given a simple password, which is why it is not taken.

# echo "mageshm:pass123" | chpasswd -e

Method-3: Creating a user without password using useradd command

You can create a password-free user on Linux using the “useradd” command.

The -p option expects a hashed password, but you are provided with a simple password, which is why it is not taken.

# useradd mageshm -s /bin/bash -p 'pass123'

Method-3.a: Using /sbin/nologin shell

User account can be created with the /sbin/ nologin shell option. This shell usually does not allow the user to log in to the computer.

# useradd -s /sbin/nologin mageshm

You will receive the following message when you attempt to switch the account from the root.

# su - mageshm This account is currently not available.

Method-3.b: Changing the shell to false

We can use the /bin/false option with the “useradd” command to create a new user without password. ‘/bin/false’ is just a binary that immediately exits, returning false, when it’s called. The user logs in and immediately sees the login prompt again.

This shell works exactly like the one above, and it does not allow the user to log in to the computer.

# useradd -s /bin/false mageshm

When you try to switch the account from the root you get nothing.

Method-3.c: Changing the shell to /dev/null

‘/dev/null’ is a simple device which is implemented in software and doesn’t correspond to any hardware device on the system.

dev/null looks empty when you read from it, whereas data written to this device simply “disappears.”

User can be disabled by changing the shell to /dev/null as shown below:

Closing Notes

You learnt different ways to create a user without a password in Linux.

If you found this article helpful, please do share with your friends and spread the knowledge. Please feel free to comment below if you have any queries/concerns. We will get back to you as soon as we can. Happy learning!

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How to Enable No Password Login in Ubuntu, Fedora, Manjaro & Linux Mint

This simple tutorial shows how to enable password-less login for specific user in Linux PC. So, user doesn’t have to remember the password, just a single click will let in.

It’s easy to enable automatic login, even with a few seconds delay. But for multiple accounts (e.g., guest or user account for kids), remove the password authentication could be a better choice.

This tutorial is tested and works in Ubuntu 22.04, Ubuntu 20.04, Fedora 36, Manjaro GNOME, and Linux Mint 20/21

Requirements:

To enable this feature, you need login with a user account that has the ability to edit system config file (aka, administrator).

As well, new user account must have been login for the first time to generate user’s home folder.

Enable no password login for specific user:

1. Firstly, open terminal by either pressing Ctrl+Alt+T on keyboard (works in Ubuntu/Linux Mint), or searching from start menu or “Activities” overview.

2. When terminal opens, run the command below to edit the config file:

sudo gedit /etc/pam.d/gdm-password

Tip 1: For Ubuntu 22.10+ and Fedora 36 replace gedit with gnome-text-editor, so the command will be: sudo gnome-text-editor /etc/pam.d/gdm-password Tip 2: This is for GNOME only, other desktop may have another config file under "/etc/pam.d" directory, such as "/etc/pam.d/lightdm" for Mint. Tip 3: Linux Mint user DON'T have to edit any config file. Just run bottom command to add user into 'nopasswdlogin' group.

3. When the config file opens, add the rule to the first line:

auth sufficient pam_succeed_if.so user = merilyn

Replace merilyn with the desired username and save the file!

That’s it! After saving the file, restart computer and click the username in login screen to see the magic!

Password-less login for a group of users:

Besides writing multiple lines in previous config file, you may add users to a certain group, and set to allow all users in that group to login without password.

1. First, open terminal and run command to create “nopasswdlogin” group.

sudo groupadd nopasswdlogin

2. Next, edit the config file via command:

sudo gedit /etc/pam.d/gdm-password

Replace gedit with your system text editor, such as gnome-text-editor for Fedora 36/Ubuntu22.10.

Add the line below and save it:

auth sufficient pam_succeed_if.so user ingroup nopasswdlogin

NOTE: Linux Mint only need to do last command in step 3 as 'nopasswdlogin' group already exist and well configured.

3. Finally, add (or remove) any user into/from that group ( nopasswdlogin ) to enable (or disable) password-less login.
For example, add user ‘merilyn’ to the group via command:

sudo gpasswd --add merilyn nopasswdlogin

replace —add with —delete will remove user from the group

Restart your machine to apply changes and done!

Summary:

Thing is quite easy in short. Just edit the configuration file under “/etc/pam.d” directory. Then add a rule to either allow certain user or all users from a group to login without password authentication. Linux Mint has a ‘nopasswdlogin’ group set for this stuff out-of-box, so simply add a user into that group can do the trick!

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How to login to Ubuntu 18.04 without a password

I have just upgraded to Ubuntu 18.04 from 16.04 and I appear to have lost my ability to login without a password. This is something that I used in 16.04 for a media player computer that I have in my living room. This question appears to have been asked before, and has been marked as a duplicated here: How can I log in to Ubuntu 18.04 without a password? Setting auto login doesn’t work However, the answers are about auto-login and I do not want this. I want to get a login dialog with a user name that requires no password, not one that auto-logins in on boot. This is so that I can choose which account to login in to (I have one account for playing media and my own «real» account which I use for sys admin), or so that I can choose session types (my media account mostly uses kodi, but sometimes I need a desktop). This was possible with previous versions of Ubuntu: http://ubuntuhandbook.org/index.php/2013/07/login-without-a-password-on-ubuntu/ Has it been lost in 18.04?

2 Answers 2

I do exactly this myself, and upgraded the box from 16.04 to 18.04 a few weeks ago — with zero ill effects.

Run sudo passwd -d username to delete the password for this user.

That should allow you to login without entering a password, and works fine for me on 18.04

If this is your only account on the machine, you should probably either configure passwordless sudo, or add a second account with administrative privileges.

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Creating a user without a password

Nothing is wrong, the authentication failed as expected. You won’t get a «there is no password, you can’t login» error message.

Either create it as root and set the correct permissions, or execute su git as root where you don’t have to provide a password.

I just wanted to point out that letting the git user have Bash as a shell is a bad idea, security wise. That would allow users of this repo to get a shell in your server. If you set the shell to /usr/bin/git-shell you can limit their account to using git and nothing else. (You should also limit SFTP access but that can only be done from /etc/sshd_config). Now, once you changed the shell, «su» won’t work as-is. You’ll have to do «su -s /bin/sh git» instead.

7 Answers 7

The —disabled-password option will not set a password, meaning no password is legal, but login is still possible (for example with SSH RSA keys).

To create an user without a password, use passwd -d $username after the user is created to make the password empty. Note not all systems allow users with empty password to log in.

You’ve created a user with a “disabled password”, meaning that there is no password that will let you log in as this user. This is different from creating a user that anyone can log in as without supplying a password, which is achieved by specifying an empty password and is very rarely useful.

In order to execute commands as such “system” users who don’t log in normally, you need to hop via the root account:

If you want certain users to be able to run commands as the git user without letting them run commands as root, set up sudo (run visudo as root and add a line like %gitters ALL = (git) ALL ).

Ubuntu 19.10 seems like does not have —disabled-password parameter, could there be any alternative solution

@alper Write the full path: sudo -u git cat /wherever/main.py . Or add a cd command: sudo -u git sh -c ‘cd /wherever && cat main.py’ . If you want to be sure that the other user doesn’t get access to the current directory even if the command doesn’t do what was intended, change directories outside: (cd /wherever && sudo -u git cat main.py)

@alper You didn’t use the commands I posted. You used one of many variants (too many for me to guess the exact one) that would result in this particular error. You need to invoke a shell for cd and && .

If you want to access the system under the git user you should use sudo:

Create an user with empty password

sudo useradd test-user-0 echo test-user-0:U6aMy0wojraho | sudo chpasswd -e su test-user-0 

The password prompt still shows unfortunately.

But if you just hit enter without typing anything, and it logins as the user test-user-0 .

The -e flags tells chpasswd that the password is already encrypted, and U6aMy0wojraho is the hash of the empty string.

Terminal autologin with getty -a

On the terminal at least, you don’t need to create an user without a password to allow someone to not type their passwords every time.

So I believe that it should not be very hard to adapt that technique by modifying Ubuntu 18.04’s systemd init system scripts to setup a getty -a terminal as mentioned in that answer, although I haven’t tried to do it myself.

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