How to Switch Between Users Without Password in Linux August 1, 2025

This guide explains how to switch between users without a password in Linux.

Switching users in Linux usually requires entering a password. However, there are safe ways to configure your system to allow certain users to switch accounts without a password prompt. This can be useful for administrative scripts, automation, or trusted environments.

Using ‘sudo’ Without a Password
 A common method is configuring sudo to allow a specific user-switching command without a password. Access should be restricted to only the commands required, following the principle of least privilege.

1. Edit the sudoers file
   Open the sudoers file using the visudo command:

   sudo visudo

2. Add a passwordless entry
   Add the below line at the termination of the file:

   username ALL=(targetuser) NOPASSWD:  /bin/su - targetuser

   • username ? The current user.
   • targetuser ? The user you want to switch to.
   • Warning Avoid using: 

     username ALL=(targetuser) NOPASSWD: ALL 

     This configuration allows the specified user to execute any command as targetuser without authentication. 

     If targetuser is root or another privileged account, this effectively grants full administrative access and may introduce privilege-escalation risks. 

     Whenever possible, restrict NOPASSWD permissions to the specific command required for user switching.

3. Switch user
   Now you can switch users without entering a password:

   sudo -u targetuser -i

   Or:

   sudo su - targetuser

These commands should only be permitted through narrowly scoped sudoers rules. Avoid granting NOPASSWD: ALL unless unrestricted access has been explicitly approved. 

Using ‘su’  With Passwordless Access (Optional)
You can let ‘su’ switch users without a password by changing PAM (Pluggable Authentication Modules). Warning: This process is less protected.

1. Backup PAM configuration

   sudo cp /etc/pam.d/su /etc/pam.d/su.bak

2. Edit PAM configuration
   Open the file:

   sudo nano /etc/pam.d/su

   Comment out the line:

   auth       required   pam_wheel.so

   Or adjust it according to your distro to allow specific users.
   Note: This is not recommended on production systems due to security risks.

Using SSH Key-Based Authentication (For Remote Switching)
If switching users remotely via SSH:

1. Generate SSH keys

   ssh-keygen -t rsa

2. Copy the public key to the target user:

   ssh-copy-id targetuser@localhost

3. Switch user via SSH without a password:

   ssh targetuser@localhost

Security Considerations:

• Only grant passwordless access to trusted users.
• Avoid enabling passwordless su in production environments.
• Prefer narrowly scoped sudoers rules that allow only the specific command required for user switching. 

  Avoid NOPASSWD: ALL because it grants unrestricted command execution as the target account and can lead to privilege escalation. 

• Always back up configuration files before editing.

This way, you can switch between users without a password in Linux.  Hope you liked our article. If you want additional assistance, feel free to contact our support staff.

Want easier access too? Learn How to Enable Passwordless SSH Login in Linux