UBTU-22-412040 Ubuntu 22.04 LTS must not assign an interactive login shell for system accounts.
All changes in this version
Maps to SI-6 via CCI-002696
Title
Ubuntu 22.04 LTS must not assign an interactive login shell for system accounts.
Control
Verify Ubuntu 22.04 LTS system accounts do not have an interactive login shell with the following command: Run the following command to list any system account (UID 0 && $3 < 1000) && $1 !~ /^(halt|sync|shutdown)$/ && $7 !~ /(nologin|false)$/) {print $1 ":" $3 ":" $7}' /etc/passwd If the command returns any output, this is a finding.
Discussion
Ensuring shells are not given to system accounts upon login makes it more difficult for attackers to use system accounts.
Related controls
CCI-002696
Fix
Configure Ubuntu 22.04 LTS so that all noninteractive accounts on the system do not have an interactive shell assigned to them. If the system account needs a shell assigned for mission operations, document the need with the information system security officer (ISSO). Run the following command to disable the interactive shell for a specific noninteractive user account: $ sudo usermod -s /usr/sbin/nologin