====== 1.4.3 Ensure authentication required for single user mode (Not Scored) ====== =====Profile Applicability===== Level 1 - Server Level 1 - Workstation =====Description===== Single user mode (rescue mode) is used for recovery when the system detects an issue during boot or by manual selection from the bootloader. =====Rationale===== Requiring authentication in single user mode (rescue mode) prevents an unauthorized user from rebooting the system into single user to gain root privileges without credentials. =====Audit===== Run the following commands and verify that ''/sbin/sulogin'' is used as shown: # grep /sbin/sulogin /usr/lib/systemd/system/rescue.service ExecStart=-/bin/sh -c "/sbin/sulogin; /usr/bin/systemctl --fail --no-block default" # grep /sbin/sulogin /usr/lib/systemd/system/emergency.service ExecStart=-/bin/sh -c "/sbin/sulogin; /usr/bin/systemctl --fail --no-block default" =====Remediation===== Edit ''/usr/lib/systemd/system/rescue.service'' and ''/usr/lib/systemd/system/emergency.service'' and set ''ExecStart'' to use ''/sbin/sulogin'': ExecStart=-/bin/sh -c "/sbin/sulogin; /usr/bin/systemctl --fail --no-block default"