Which file lists users who are allowed to use sudo

Which file lists users who are allowed to use sudo - CompTIA Linux + XK0-005

Question

Which file lists users who are allowed to use sudo?

Answers

/etc/shadow
correct

/etc/sudoers
/etc/groups
/etc/passwd

Explanation

Correct Answer: b. /etc/sudoers

The /etc/sudoers file is the primary configuration file that determines which users and groups have permission to execute commands with sudo privileges. It defines access policies, command permissions, and privilege escalation rules.

Proper editing of this file is crucial and should be done using visudo to avoid syntax errors that could lock administrators out of sudo access, thereby preventing accidental misconfiguration of critical system permissions.

why the other options are incorrect:

a. /etc/shadow: This file stores encrypted user password hashes and account expiration data. It does not define sudo privileges and cannot be used to control user access to administrative commands.
c. /etc/groups: While this file lists group memberships, including the sudo or wheel group (depending on the system), it doesn't itself assign sudo privileges. It must be used in conjunction with /etc/sudoers to enable group-based sudo access.
d. /etc/passwd: This file contains user account information such as usernames, UIDs, home directories, and default shells. It does not control sudo access or define administrative privileges.