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User Account Control: Behavior of the elevation prompt for standard users

 

Applies To: Windows Server 2003, Windows Vista, Windows XP, Windows Server 2008, Windows 7, Windows 8.1, Windows Server 2008 R2, Windows Server 2012 R2, Windows Server 2012, Windows 8

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 the behavior of the elevation prompt for standard users.

Possible values

  • Automatically deny elevation requests

    This option returns an “Access denied” error message to standard users when they try to perform an operation that requires elevation of privilege. Most enterprises that run desktops as standard users configure this policy to reduce Help Desk calls.

  • Prompt for credentials on the secure desktop

    This is the default. When an operation requires elevation of privilege, the user is prompted on the secure desktop to enter a different user name and password. If the user enters valid credentials, the operation continues with the applicable privilege.

  • Prompt for credentials

    An operation that requires elevation of privilege prompts the user to type an administrative user name and password. If the user enters valid credentials, the operation continues with the applicable privilege.

Best practices

  1. Configure the User Account Control: Behavior of the elevation prompt for standard users to Automatically deny elevation requests. This setting requires the user to log on with an administrative account to run programs that require elevation of privilege.

  2. As a security best practice, standard users should not have knowledge of administrative passwords. However, if your users have both standard and administrator-level accounts, set Prompt for credentials so that the users do not choose to always log on with their administrator accounts, and they shift their behavior to use the standard user account.

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

Prompt for credentials on the secure desktop

DC Effective Default Settings

Prompt for credentials on the secure desktop

Member Server Effective Default Settings

Prompt for credentials on the secure desktop

Client Computer Effective Default Settings

Prompt for credentials on the secure desktop

Operating system version differences

The default in Windows Vista and Windows Server 2008 is Prompt for credentials. In Windows Server 2008 R2 and Windows 7, the default is changed to Prompt for credentials on the secure desktop.

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

Distributing this policy through Group Policy to operating systems earlier than Windows Vista and Windows Server 2008 will have no impact (because UAC was first introduced in Windows Vista).

Distributing this policy to computers running Windows Vista and Windows Server 2008 will change the default option to Prompt for credentials on the secure desktop. You will need to test that the resultant behavior is as you expect.

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

One of the risks that the UAC feature tries to mitigate is that of malicious programs running under elevated credentials without the user or administrator being aware of their activity. This setting raises awareness to the user that a program requires the use of elevated privilege operations, and it requires that the user supply administrative credentials for the program to run.

Countermeasure

Configure the User Account Control: Behavior of the elevation prompt for standard users to Automatically deny elevation requests. This setting requires the user to log on with an administrative account to run programs that require elevation of privilege. As a security best practice, standard users should not have knowledge of administrative passwords. However, if your users have both standard and administrator-level accounts, we recommend setting Prompt for credentials so that the users do not choose to always log on with their administrator accounts,and they shift their behavior to use the standard user account.

Potential impact

Users must provide administrative passwords to run programs with elevated privileges. This could cause an increased load on IT staff while the programs that are affected are identified and standard operating procedures are modified to support least privilege operations.