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
V-17442	WN08-FW-000025	SV-48402r1_rule	ECSC-1	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
Windows 8 Security Technical Implementation Guide	2013-02-15

Details

Check Text ( C-45071r2_chk )
If the following registry value does not exist or is not configured as specified, this is a finding: Registry Hive: HKEY_LOCAL_MACHINE Subkey: \Software\Policies\Microsoft\WindowsFirewall\PublicProfile\ Value Name: AllowLocalPolicyMerge Type: REG_DWORD Value: 0 Note: If a third-party firewall is used, document this with the IAO and mark the Windows firewall settings as NA. A comparable setting must still be implemented. The Secure Remote Computing STIGs may contain additional requirements for systems used remotely.

Check Text ( C-45071r2_chk )

If the following registry value does not exist or is not configured as specified, this is a finding:

Registry Hive: HKEY_LOCAL_MACHINE
Subkey: \Software\Policies\Microsoft\WindowsFirewall\PublicProfile\

Value Name: AllowLocalPolicyMerge

Type: REG_DWORD
Value: 0

Note: If a third-party firewall is used, document this with the IAO and mark the Windows firewall settings as NA. A comparable setting must still be implemented. The Secure Remote Computing STIGs may contain additional requirements for systems used remotely.

Fix Text (F-41533r1_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".