The Windows Firewall local firewall rules must not be merged with Group Policy settings for the Public Profile.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
WN12-FW-000025	WN12-FW-000025	WN12-FW-000025_rule		Medium

Description
A firewall provides a line of defense against attack. To be effective, it must be enabled and properly configured. Local firewall rules will not be merged with Group Policy settings on a public network to prevent Group Policy settings from being changed.

STIG	Date
Microsoft Windows Server 2012 Domain Controller Security Technical Implementation Guide	2013-07-25

Details

Check Text ( C-WN12-FW-000025_chk )
If the following registry value does not exist or is not configured as specified, this is a finding: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \Software\Policies\Microsoft\WindowsFirewall\PublicProfile\ Value Name: AllowLocalPolicyMerge Type: REG_DWORD Value: 0 If a third-party firewall is used, verify a comparable setting has been implemented.

Fix Text (F-WN12-FW-000025_fix)
Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Windows Firewall with Advanced Security -> Windows Firewall with Advanced Security -> Windows Firewall Properties (this link will be in the right pane) -> Public Profile Tab -> Settings (select Customize) -> Rule merging, "Apply local firewall rules:" to "No". Configure a comparable setting if a third-party firewall is used.

Fix Text (F-WN12-FW-000025_fix)

Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Windows Firewall with Advanced Security -> Windows Firewall with Advanced Security -> Windows Firewall Properties (this link will be in the right pane) -> Public Profile Tab -> Settings (select Customize) -> Rule merging, "Apply local firewall rules:" to "No".

Configure a comparable setting if a third-party firewall is used.