Vulnerability Discussion

If auditing is enabled late in the startup process, the actions of some startup processes may not be audited. Some audit systems also maintain state information only available if auditing is enabled before a given process is created.

Check

Verify that Ubuntu 22.04 LTS enables auditing at system startup in grub by using the following command:

$ sudo grep -ir GRUB_CMDLINE_LINUX /etc/default/grub
/etc/default/grub:GRUB_CMDLINE_LINUX_DEFAULT="audit=1"
/etc/default/grub:GRUB_CMDLINE_LINUX="audit=1"

If any linux lines do not contain "audit=1", this is a finding.

Note: Output may vary by system.

Fix

Configure the Ubuntu operating system to produce audit records at system startup.

Edit the "/etc/default/grub" file and add "audit=1" to the "GRUB_CMDLINE_LINUX" option and to the "GRUB_CMDLINE_LINUX_DEFAULT" option.

GRUB_CMDLINE_LINUX_DEFAULT="audit=1"
GRUB_CMDLINE_LINUX="audit=1"

To update the grub config file, run:

$ sudo update-grub