auth_pam_su_smartcard_enforce Enforce Multifactor Authentication for the su Command
All changes in this version
Title
Enforce Multifactor Authentication for the su Command
Control
/usr/bin/grep -Ec '^(auth\s+sufficient\s+pam_smartcard.so|auth\s+required\s+pam_rootok.so)' /etc/pam.d/su
Discussion
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 require 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.
Related controls
ia-2.1, ia-2.2, ia-2.8
Fix
[source,bash]
----
/bin/cat > /etc/pam.d/su << SU_END
# su: auth account password session
auth sufficient pam_smartcard.so
auth required pam_rootok.so
auth required pam_group.so no_warn group=admin,wheel ruser root_only fail_safe
account required pam_permit.so
account required pam_opendirectory.so no_check_shell
password required pam_opendirectory.so
session required pam_launchd.so
SU_END
# Fix new file ownership and permissions
/bin/chmod 644 /etc/pam.d/su
/usr/sbin/chown root:wheel /etc/pam.d/su
----