18

Whenever I issue command sudo apt-get install foo it does not ask for password. is it because of user groups?

How to make it prompt for password?

Edit: My sudoers file

apple@Ascension:~$ sudo cat /etc/sudoers
#
# This file MUST be edited with the 'visudo' command as root.
#
# Please consider adding local content in /etc/sudoers.d/ instead of
# directly modifying this file.
#
# See the man page for details on how to write a sudoers file.
#
Defaults    env_reset

# Host alias specification

# User alias specification

# Cmnd alias specification

# User privilege specification
root    ALL=(ALL:ALL) ALL

# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL

# Allow members of group sudo to execute any command
%sudo   ALL=(ALL:ALL) ALL

#includedir /etc/sudoers.d
ALL ALL=(ALL) NOPASSWD:ALL
ALL ALL=(ALL) NOPASSWD:ALL
ALL ALL=(ALL) NOPASSWD:ALL
Radu Rădeanu
  • 174,437
Rahul Virpara
  • 11,880

1 Answers1

19

With the command sudo visudo you can see and edit, the sudo configuration, for example :

# User privilege specification
root    ALL=(ALL:ALL) ALL

# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL

# Allow members of group sudo to execute any command
%sudo   ALL=(ALL:ALL) ALL

# Group without password
%nopwd  ALL=NOPASSWD: ALL

Your current user is probably member of a privileged group that enables him to enter sudo commands without password. In this example members of admin and sudo group can issue any command with sudo, but are prompted with a password ; members of the nopwd group are not prompted with a password.

Note that the declaration order is relevant for users belonging to multiple groups. Unintuitively, the LAST matching group wins !

In order to require a password, you can add the PASSWD: /usr/bin/apt-get command specification in file /etc/sudoers ; note that you probably want to allow specific commands with no password, and keep every other command with a password. An example explicitely requesting a password for apt-get:

%users  ALL=NOPASSWD: /sbin/reboot, PASSWD: /usr/bin/apt-get

Note that you can personnalize sudo with a much finer granularity than allow all commands like in my first example (doc ubuntu fr)(doc ubuntu en).

JB.
  • 809
  • Okay. My sudo didn't ask for a password, but when I entered sudo visudo it asked for my password and does ever since? Maybe changing my password to the same as the one I set during KDE Neon clean-install just hours earlier fixed the problem… – Lampe2020 Jun 20 '24 at 01:54
  • @Lampe2020 It could be that it removed the timestamp. sudo will not ask for a password for a set period of time after the last time you used sudo. You can manually remove the timestamp file by running sudo -K to basically revoke this so that it will ask for a password again the next time you run sudo regardless of when you last ran sudo. – mchid Aug 05 '25 at 17:31