Title

The system's boot loader configuration file(s) must not have extended ACLs. (Cat II impact)

Discussion

File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files. If extended ACLs are present on the system's boot loader configuration file(s), these files may be vulnerable to unauthorized access or modification, which could compromise the system's boot process.

Check Content

This check applies to the global zone only. Determine the type zone that you are currently securing. # zonename If the command output is "global", this check applies. On systems that have a ZFS root, the active menu.lst file is typically located at /pool-name/boot/grub/menu.lst where "pool-name" is the mount point for the top-level dataset. On systems that have a UFS root, the active menu.lst file is typically located at /boot/grub/menu.lst. To locate the active GRUB menu, use the bootadm command with the list-menu option: # bootadm list-menu Check the permissions of the menu.lst file. Procedure: # ls -lL /pool-name/boot/grub/menu.lst or # ls -lL /boot/grub/menu.lst If the permissions of the menu.lst file contain "+", an extended ACL is present, and this is a finding.

Fix Text

If the file with the extended ACL resides on a UFS filesystem: # getfacl /boot/grub/menu.lst Remove each ACE from the file. # setfacl -r [ACE] /boot/grub/menu.lst If the file with the extended ACL resides on a ZFS filesystem: # chmod A- /pool-name/boot/grub/menu.lst

Additional Identifiers

Rule ID: SV-220127r603266_rule

Vulnerability ID: V-220127

Group Title: SRG-OS-000480

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.