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Shutdown: Allow system to be shut down without having to log on

Updated: November 15, 2012

Applies To: Windows 7, Windows Server 2003, Windows Server 2008, Windows Server 2008 R2, Windows Vista, Windows XP

This security policy reference topic for the IT professional describes the best practices, location, values, policy management and security considerations for this policy setting.

Reference

This policy setting determines whether a computer can be shut down without having to log on to the Windows operating system. If you enable this policy setting, the Shut Down option is available on the logon screen in the Windows operating system. If you disable this policy setting, the Shut Down option is removed from the logon screen. This configuration requires that users are able to log on to the computer successfully and that they have the Shut down the system user right before they can perform a computer shutdown.

Users who can access the console locally can shut down the system. Attackers or misguided users can connect to the server by using Terminal Services or Remote Desktop Services, and then shut it down or restart it without having to identify themselves. A malicious user might also cause a temporary denial-of-service condition by walking up to the local console and restarting the server, or shutting down the server and thus rendering unavailable all its applications and services.

Possible values

  • Enabled

    The Shut Down command is available on the logon screen in the Windows operating system.

  • Disabled

    The Shut Down option is removed from the logon screen and users must have the Shut down the system user right before they can perform a computer shutdown.

  • Not defined

Best practices

  1. On servers, set this policy to Disabled. Administrators must log on to servers to shut them down or restart them.

  2. On client computers, set this policy to Enabled and define the list of those with the right to shut them down or restart them with the User Rights Assignment policy Shut down the system.

Location

GPO_name\Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options

Default values

The following table lists the actual and effective default values for this policy. Default values are also listed on the policy’s property page.

Server type or GPO Default value

Default Domain Policy

Not defined

Default Domain Controller Policy

Not defined

Stand-Alone Server Default Settings

Disabled

DC Effective Default Settings

Disabled

Member Server Effective Default Settings

Disabled

Client Computer Effective Default Settings

Enabled

Operating system version differences

There are no differences in this policy between operating systems beginning with Windows Server 2008 and Windows Vista.

Policy management

This section describes features and tools that are available to help you manage this policy.

Restart requirement

None. Changes to this policy become effective without a computer restart when they are saved locally or distributed through Group Policy.

Group Policy

For information about the User Rights Assignment policy, Shut down the system, see the Shut down the system reference topic.

Security considerations

This section describes how an attacker might exploit a feature or its configuration, how to implement the countermeasure, and the possible negative consequences of countermeasure implementation.

Vulnerability

Users who can access the console locally could shut down the computer.

Attackers who have access to the local console could restart the server, which would cause a temporary DoS condition. Attackers could also shut down the server and leave all of its applications and services unavailable.

Countermeasure

Disable the Shutdown: Allow system to be shut down without having to log on setting.

Potential impact

Operators must log on to servers to shut them down or restart them.