IPSec Exemptions must be limited.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
WN08-SO-000042	WN08-SO-000042	WN08-SO-000042_rule		Low

Description
IPSec exemption filters allow specific traffic that may be needed by the system for such things as Kerberos authentication. This setting configures Windows for specific IPSec exemptions.

STIG	Date
Windows 8 Security Technical Implementation Guide	2012-11-21

Details

Check Text ( C-WN08-SO-000042_chk )
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: (NoDefaultExempt) Configure IPSec exemptions for various types of network traffic" is not set to "Multicast, broadcast and ISAKMP exempt (best for Windows XP)", this is a finding. The policy referenced configures the following registry value: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \System\CurrentControlSet\Services\IPSEC\ Value Name: NoDefaultExempt Value Type: REG_DWORD Value: 1

Check Text ( C-WN08-SO-000042_chk )

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: (NoDefaultExempt) Configure IPSec exemptions for various types of network traffic" is not set to "Multicast, broadcast and ISAKMP exempt (best for Windows XP)", this is a finding.

The policy referenced configures the following registry value:

Registry Hive: HKEY_LOCAL_MACHINE
Registry Path: \System\CurrentControlSet\Services\IPSEC\

Value Name: NoDefaultExempt

Value Type: REG_DWORD
Value: 1

Fix Text (F-WN08-SO-000042_fix)
Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> Security Options -> "MSS: (NoDefaultExempt) Configure IPSec exemptions for various types of network traffic" to "Multicast, broadcast and ISAKMP exempt (best for Windows XP)".