1.4.3 Ensure authentication required for single user mode - rescue

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.

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.

Solution

Edit /usr/lib/systemd/system/rescue.service and /usr/lib/systemd/system/emergency.service and set ExecStart to use '/usr/sbin/sulogin': ExecStart=-/bin/sh -c "/usr/sbin/sulogin; /usr/bin/systemctl --job-mode=fail --no-block default"

Notes:
The systemctl option --fail is synonymous with --job-mode=fail. Using either is acceptable.

See Also

https://workbench.cisecurity.org/files/1865

Item Details

Category: SYSTEM AND INFORMATION INTEGRITY

References: 800-53|SI-7(9)

Plugin: Unix

Control ID: 353fe1bb31cab34b099bb261bcec857b719879e100a2f64078f3fe8f8ef0182e