Title

The system must be configured to have password protection take effect within a limited time frame when the screen saver becomes active. (Cat III impact)

Discussion

Allowing more than several seconds makes the computer vulnerable to a potential attack from someone walking up to the console to attempt to log onto the system before the lock takes effect.

Check Content

Analyze the system using the Security Configuration and Analysis snap-in. (See "Performing Analysis with the Security Configuration and Analysis Snap-in" in the STIG Overview document.) Expand the Security Configuration and Analysis tree view. Navigate to Local Policies -> Security Options. (See "Updating the Windows Security Options File" in the STIG Overview document if MSS settings are not visible in the system's policy tools.) If the value for "MSS: (ScreenSaverGracePeriod) The time in seconds before the screen saver grace period expires (0 recommended)" is not set to "5" or less, this is a finding. The policy referenced configures the following registry value: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \Software\Microsoft\Windows NT\CurrentVersion\Winlogon\ Value Name: ScreenSaverGracePeriod Value Type: REG_SZ Value: 5 (or less)

Fix Text

Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> Security Options -> "MSS: (ScreenSaverGracePeriod) The time in seconds before the screen saver grace period expires (0 recommended)" to "5" or less.

Additional Identifiers

Rule ID: SV-48128r1_rule

Vulnerability ID: V-4442

Group Title: Screen Saver Grace Period

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.