1.5.3 Ensure authentication required for single user mode

Information

Single user mode (rescue mode) is used for recovery when the system detects an issue during boot or by manual selection from the bootloader.

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.

Solution

Edit /usr/lib/systemd/system/rescue.service and add/modify the following line:

ExecStart=-/bin/sh -c "/usr/sbin/sulogin; echo 'Starting default target'; /usr/bin/systemctl --job-mode=fail --no-block default"

Edit /usr/lib/systemd/system/emergency.service and add/modify the following line:

ExecStart=-/bin/sh -c "/usr/sbin/sulogin; echo 'Starting default target'; /usr/bin/systemctl --job-mode=fail --no-block default"

See Also

https://workbench.cisecurity.org/benchmarks/8498

Item Details

Category: CONFIGURATION MANAGEMENT, SYSTEM AND SERVICES ACQUISITION

References: 800-53|CM-2, 800-53|CM-6, 800-53|CM-7, 800-53|CM-7(1), 800-53|CM-9, 800-53|SA-3, 800-53|SA-8, 800-53|SA-10, CSCv7|5.1

Plugin: Unix

Control ID: 5c0c2bcd6cf492dab4b9520750f920a41281e2b16e2fc47c4eebea147112e7ec