Details

Configure SELINUX to be enabled at boot time and verify that it has not been overwritten by the grub boot parameters.

Note: This recommendation is designed around the grub 2 bootloader, if LILO or another bootloader is in use in your environment enact equivalent settings.

Rationale:

SELinux must be enabled at boot time in your grub configuration to ensure that the controls it provides are not overridden.

Solution

Edit /etc/default/grub and remove all instances of selinux=0 and enforcing=0 from all CMDLINE_LINUX parameters:

GRUB_CMDLINE_LINUX_DEFAULT=’quiet’

GRUB_CMDLINE_LINUX=”

Run the following command to update the grub2 configuration:

# grub2-mkconfig -o /boot/grub2/grub.cfg

Supportive Information

The following resource is also helpful.

• https://workbench.cisecurity.org/files/3490

This security hardening control applies to the following category of controls within NIST 800-53: Access Control, Media Protection.This control applies to the following type of system Unix.

References

• 800-53|AC-3
• 800-53|MP-2
• CSCv7|14.6

Source

• Tenable.com/audits