1.4.2 Ensure authentication required for single user mode - emergency.service

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 /sbin/sulogin or /usr/sbin/sulogin:

ExecStart=-/bin/sh -c '/sbin/sulogin; /usr/bin/systemctl --fail --no-block default'

Notes:

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

This Benchmark recommendation maps to:

Red Hat Enterprise Linux 7 Security Technical Implementation Guide:

Version 2, Release: 3 Benchmark Date: 26 Apr 2019



Vul ID: V-77823

Rule ID: SV-92519r2_rule

STIG ID: RHEL-07-010481

Severity: CAT II

See Also

https://workbench.cisecurity.org/files/2688

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6, CSCv7|5.1

Plugin: Unix

Control ID: 250f4038bb0c074ddf8702cc8bfc617266556244bb2e378322e52adb606bdac1