sudo

sudo (1980s) is a program for Unix-like computer operating systems that allows users to run programs with the security privileges of another user.

• Man page: https://man7.org/linux/man-pages/man8/sudo.8.html

Examples

• Add user to sudo group: sudo usermod -aG sudo YOUR_USERNAME
• sudo -u postgres psql

Task

• Allow user YOUR_USER_NAME to run sudo commands without typing the password:

Include in /etc/sudoers, using the visudo command, the following line at the end of the file:

YOUR_USER_NAME ALL=(ALL) NOPASSWD:ALL

• Understand order rules are applied and impact: https://vim.fandom.com/wiki/Set_Vim_as_your_default_editor_for_Unix

• Use Ansible to modify file for passwordless sudo execution in Ubuntu

Security vulnerabilities

• CVE-2019-14287 https://nvd.nist.gov/vuln/detail/CVE-2019-14287, https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-14287. CVSS Base Score: 8.8

Exploitable if the following configuration is present:

username hostname = (ALL, !root) path-to-command

Errors

sudo: unable to resolve host
See: resolv.conf

[sudo] password for USERNAME:
USERNAME is not in the sudoers file.  This incident will be reported.

Options

• -S, --stdin
• -u

Related terms

• Qualys
• sudoedit
• become_method
• SET SESSION AUTHORIZATION
• gosu
• kubectl --as

See also

• sudo, id, visudo, useradd, userdel, usermod, groups, passwd, chown, chmod, chgrp, groupadd, groupdel, Passwordless sudo, passwd (package), sudo --help
• journalctl, machinectl
• sudo, doas, Polkit (pkexec)

https://askubuntu.com/questions/192050/how-to-run-sudo-command-with-no-password