add-user-harden-ubuntu.sh

#!/bin/bash -x
set -e

# set a default new username
# if you set NEW_USERNAME="other_username" before running the script, it will use your value
NEW_USERNAME="${NEW_USERNAME:-marcus}"

# add update script
echo """doupdates () {
  export DEBIAN_FRONTEND=noninteractive
  sudo apt-get update
  sudo apt-get -y dist-upgrade
  sudo apt-get -y autoremove
  sudo apt-get -y autoclean
}""" | sudo tee -a /etc/profile
source /etc/profile

# set unattended upgrades
dpkg-reconfigure -plow unattended-upgrades

# create new user
adduser $NEW_USERNAME

# add new user to sudo group
usermod -aG sudo $NEW_USERNAME

# add to sudoers file
echo "$NEW_USERNAME ALL=(ALL) NOPASSWD: ALL" | (EDITOR="tee -a" visudo)