Partager via


Maximum password age

 

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

The Maximum password age policy setting determines the period of time (in days) that a password can be used before the system requires the user to change it. You can set passwords to expire after a number of days between 1 and 999, or you can specify that passwords never expire by setting the number of days to 0. If Maximum password age is between 1 and 999 days, the minimum password age must be less than the maximum password age. If Maximum password age is set to 0, Minimum password age can be any value between 0 and 998 days.

Note

Setting Maximum password age to -1 is equivalent to 0, which means it never expires. Setting it to any other negative number is equivalent to setting it to Not Defined.

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

Possible values

  • User-specified number of days between 0 and 999

  • Not defined

Best practices

Set Maximum password age to 60 days, depending on your environment. This way, an attacker has a limited amount of time in which to compromise a user's password and have access to your network resources.

Location

GPO_name**\Computer Configuration\Windows Settings\Security Settings\Account Policies\Password Policy** 

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.

Server type or Group Policy Object (GPO)

Default value

Default domain policy

42 days

Default domain controller policy

Not defined

Stand-alone server default settings

42 days

Domain controller effective default settings

42 days

Member server effective default settings

42 days

Effective GPO default settings on client computers

42 days

Operating system version differences

There are no differences in the way this policy setting works between supported versions of Windows.

Policy management

This section describes features, tools, and guidance 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.

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

The longer a password exists, the higher the likelihood that it will be compromised by a brute force attack, by an attacker gaining general knowledge about the user, or by the user sharing the password. Configuring the Maximum password age policy setting to 0 so that users are never required to change their passwords is a major security risk because that allows a compromised password to be used by the malicious user for as long as the valid user is authorized access.

Countermeasure

Configure the Maximum password age policy setting to a value that is suitable for your organization's business requirements.

Potential impact

If the Maximum password age policy setting is too low, users are required to change their passwords very often. Such a configuration can reduce security in the organization because users might keep their passwords in an unsecured location or lose them. If the value for this policy setting is too high, the level of security within an organization is reduced because it allows potential attackers more time in which to discover user passwords or to use compromised accounts.

See Also

Password Policy