The system must require authentication before allowing modification of the boot devices or menus. Secure the GRUB Menu (Intel).

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-216218	SOL-11.1-080140	SV-216218r505929_rule		Low

Description
The flexibility that GRUB provides creates a security risk if its configuration is modified by an unauthorized user. The failsafe menu entry needs to be secured in the same environments that require securing the systems firmware to avoid unauthorized removable media boots.

STIG	Date
Solaris 11 X86 Security Technical Implementation Guide	2020-09-03

Details

Check Text ( C-17456r373036_chk )
This check applies to X86 systems only. This check applies to the global zone only. Determine the zone that you are currently securing. # zonename If the command output is "global", this check applies. # grep source /rpool/boot/grub/grub.cfg source $prefix/custom.cfg If the output does not contain "source $prefix/custom.cfg" on a line of its own, this is a finding. # grep superusers /rpool/boot/grub/custom.cfg. # grep password_pbkdf2 /rpool/boot/grub/custom.cfg If no superuser name and password are defined, this is a finding.

Check Text ( C-17456r373036_chk )

This check applies to X86 systems only.

This check applies to the global zone only. Determine the zone that you are currently securing.

# zonename

If the command output is "global", this check applies.

# grep source /rpool/boot/grub/grub.cfg
source $prefix/custom.cfg

If the output does not contain "source $prefix/custom.cfg" on a line of its own, this is a finding.

# grep superusers /rpool/boot/grub/custom.cfg.
# grep password_pbkdf2 /rpool/boot/grub/custom.cfg

If no superuser name and password are defined, this is a finding.

Fix Text (F-17454r373037_fix)
The root role is required. This action applies to the global zone only. Determine the zone that you are currently securing. # zonename If the command output is "global", this action applies. Update GRUB to use a custom configuration file. # pfedit /rpool/boot/grub/grub.cfg Insert the line: source $prefix/custom.cfg Create a password hash. # /usr/lib/grub2/bios/bin/grub-mkpasswd-pbkdf2 Enter password: Reenter password: Your PBKDF2 is ....... Copy the long password hash in its entirety. # pfedit /rpool/boot/grub/custom.cfg Insert the lines: set superusers="[username]" password_pbkdf2 [username] [password hash] Restart the system.

Fix Text (F-17454r373037_fix)

The root role is required.

This action applies to the global zone only. Determine the zone that you are currently securing.

# zonename

If the command output is "global", this action applies.

Update GRUB to use a custom configuration file.

# pfedit /rpool/boot/grub/grub.cfg
Insert the line:
source $prefix/custom.cfg

Create a password hash.

# /usr/lib/grub2/bios/bin/grub-mkpasswd-pbkdf2
Enter password:
Reenter password:
Your PBKDF2 is .......
Copy the long password hash in its entirety.

# pfedit /rpool/boot/grub/custom.cfg
Insert the lines:
set superusers="[username]"
password_pbkdf2 [username] [password hash]

Restart the system.