Details
Single user 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 prevents an unauthorized user from rebooting the system into single user to gain root privileges without credentials.
Solution
Run the following command and follow the prompts to set a password for the root user:
# passwd root
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: Configuration Management.This control applies to the following type of system Unix.