Deny log on as a service

Applies To: Windows Vista, 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 which users are prevented from logging on to the service applications on a computer.

A service is an application type that runs in the system background without a user interface. It provides core operating system features, such as web serving, event logging, file serving, printing, cryptography, and error reporting.

This policy setting is supported on versions of Windows that are designated in the Applies To list at the beginning of this topic.

Constant: SeDenyServiceLogonRight

Possible values

• User-defined list of accounts

• Not defined

Best practices

1. When you assign this user right, thoroughly test that the effect is what you intended.

2. Within a domain, modify this setting on the applicable Group Policy Object (GPO).

Location

GPO_name\Computer Configuration\Windows Settings\Security Settings\Local Policies\User Rights Assignment

Default values

The following table lists the actual and effective default policy values for the most recent supported versions of Windows. Default values are also listed on the policy’s property page.

Operating system version differences

There are no differences in the way this policy setting works between the supported versions of Windows that are designated in the Applies To list at the beginning of this topic.

Policy management

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

A restart of the computer is not required for this policy setting to be effective.

Any change to the user rights assignment for an account becomes effective the next time the owner of the account logs on.

For information about configuring a service, see Configure How a Service Is Started.

Group Policy

On a domain-joined computer, including the domain controller, this policy can be overwritten by a domain policy, which will prevent you from modifying the local policy setting.

This policy setting might conflict with and negate the Log on as a service setting.

Settings are applied in the following order through a Group Policy Object (GPO), which will overwrite settings on the local computer at the next Group Policy update:

1. Local policy settings

2. Site policy settings

3. Domain policy settings

4. OU policy settings

When a local setting is greyed out, it indicates that a GPO currently controls that setting.

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

Accounts that can log on to a service application could be used to configure and start new unauthorized services, such as a keylogger or other malicious software. The benefit of the specified countermeasure is somewhat reduced by the fact that only users with administrative rights can install and configure services, and an attacker who has already attained that level of access could configure the service to run by using the System account.

Countermeasure

We recommend that you not assign the Deny log on as a service user right to any accounts. This is the default configuration. Organizations that are extremely concerned about security might assign this user right to groups and accounts when they are certain that they will never need to log on to a service application.

Potential impact

If you assign the Deny log on as a service user right to specific accounts, services may not start and a denial-of-service condition could result.

See Also

User Rights Assignment