3.6 Ensure 'Password expiration' is set to '365' or less

Information

This policy setting is used to specify how long before a password expires.

Rationale:

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 this setting to 0 so that users are never required to change their passwords is a major security risk because doing so allows a compromised password to be used by a malicious user for as long as the valid user has authorized access to the system.

Impact:

Configuring the value of this setting too low requires users to change their passwords very often. This can reduce security in the organization, because users might write their passwords in an unsecured location or lose them. Configuring the value of this setting too high also reduces the level of security in an organization, because it allows potential attackers more time to discover user passwords or to use compromised accounts.

Note: This is a mobile device management setting. Use caution when applying these settings as they could have adverse effects depending on the environment, and internal policies around bring your own device (BYOD). These policies could affect a user's BYOD.

Solution

To implement the recommended state, execute the following PowerShell cmdlet:

Set-MobileDeviceMailboxPolicy 'Profile' -PasswordExpiration 90

OR

Perform the following actions:

Launch the EAC (Exchange Administrative Center).

Go to 'Mobile' on the left and click on the 'Mobile device mailbox policies' tab.

Double-click the policy you wish to modify and go to the 'Security' settings.

Ensure the Enforce password lifetime (days) box is checked change the value to 365 and click Save

Default Value:

Unlimited

See Also

https://workbench.cisecurity.org/benchmarks/12442

Item Details

Category: IDENTIFICATION AND AUTHENTICATION

References: 800-53|IA-5(1), CSCv7|4.4

Plugin: Windows

Control ID: 0dcc92eb237d3affb326b2d6aad7f101e6e0b620ec873a6adfcd0c48d300b1f2