macOS 15 - Sequoia
The macOS system must enforce multifactor authentication for the su command
Description
The system must be configured such that, when the su command is used, multifactor authentication is enforced.All users must go through multifactor authentication to prevent unauthenticated access and potential compromise to the system.IMPORTANT: Modification of Pluggable Authentication Modules (PAM) now requires user authorization or use of a Privacy Preferences Policy Control (PPPC) profile from MDM that authorizes modifying system administrator files or full disk access.NOTE: /etc/pam.d/su will be automatically modified to its original state following any update or major upgrade to the operating system.Satisfies: SRG-OS-000105-GPOS-00052, SRG-OS-000106-GPOS-00053, SRG-OS-000107-GPOS-00054, SRG-OS-000108-GPOS-00055, SRG-OS-000112-GPOS-00057, SRG-OS-000705-GPOS-00150
Check
Verify the macOS system is configured to enforce multifactor authentication for the su command with the following command:/usr/bin/grep -Ec '^(auth\s+sufficient\s+pam_smartcard.so|auth\s+required\s+pam_rootok.so)' /etc/pam.d/suIf the result is not "2", this is a finding.
Fix
Configure the macOS system to enforce multifactor authentication for the su command with the following commands:/bin/cat > /etc/pam.d/su << SU_END# su: auth account password sessionauth sufficient pam_smartcard.soauth required pam_rootok.soauth required pam_group.so no_warn group=admin,wheel ruser root_only fail_safeaccount required pam_permit.soaccount required pam_opendirectory.so no_check_shellpassword required pam_opendirectory.sosession required pam_launchd.soSU_END# new file ownership and permissions/bin/chmod 644 /etc/pam.d/su/usr/sbin/chown root:wheel /etc/pam.d/su