BOOT-5260 - Single user mode for systemd

(Authentication)

This information is provided as part of the Lynis community project. It is related to Lynis control BOOT-5260 and should be considered as-is and without guarantees. Any advice and commands should be tested before implementing them in production environments.

Description

Systemd has a single user mode, named rescue.service. Similar to normal single user mode, it allows access to the system and bypass several levels of authorization. To protect against this, reconfigure the service with the sulogin option.

How to solve

Change your rescue.service file (/usr/lib/systemd/system/rescue.service) and define sulogin. ExecStart=-/usr/sbin/sulogin Note: ensure that it is linking to the right sulogin binary, which can change between distributions.

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