Ubuntu 22.04 LTS must be configured so that the Advance Package Tool (APT) removes all software components after updated versions have been installed.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-260477	SRG-OS-000437-GPOS-00194	UBTU-22-214015	SV-260477r1044773_rule	2025-03-03	2

Description
Previous versions of software components that are not removed from the information system after updates have been installed may be exploited by adversaries. Some information technology products may remove older versions of software automatically from the information system.

ℹ️ Check
Verify APT is configured to remove all software components after updated versions have been installed by using the following command: $ grep -i remove-unused /etc/apt/apt.conf.d/50unattended-upgrades Unattended-Upgrade::Remove-Unused-Kernel-Packages "true"; Unattended-Upgrade::Remove-Unused-Dependencies "true"; If "Unattended-Upgrade::Remove-Unused-Kernel-Packages" and "Unattended-Upgrade::Remove-Unused-Dependencies" are not set to "true", are commented out, or are missing, this is a finding.

ℹ️ Check

Verify APT is configured to remove all software components after updated versions have been installed by using the following command: $ grep -i remove-unused /etc/apt/apt.conf.d/50unattended-upgrades Unattended-Upgrade::Remove-Unused-Kernel-Packages "true"; Unattended-Upgrade::Remove-Unused-Dependencies "true"; If "Unattended-Upgrade::Remove-Unused-Kernel-Packages" and "Unattended-Upgrade::Remove-Unused-Dependencies" are not set to "true", are commented out, or are missing, this is a finding.

✔️ Fix
Configure APT to remove all software components after updated versions have been installed. Add or modify the following lines in the "/etc/apt/apt.conf.d/50unattended-upgrades" file: Unattended-Upgrade::Remove-Unused-Kernel-Packages "true"; Unattended-Upgrade::Remove-Unused-Dependencies "true";