Zone information must be preserved when saving attachments.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-63841	WN10-UC-000020	SV-78331r2_rule		Medium

Description
Preserving zone of origin (internet, intranet, local, restricted) information on file attachments allows Windows to determine risk.

STIG	Date
Windows 10 Security Technical Implementation Guide	2017-02-21

Details

Check Text ( C-72015r2_chk )
The default behavior is for Windows to mark file attachments with their zone information. If the registry Value Name below does not exist, this is not a finding. If it exists and is configured with a value of "2", this is not a finding. If it exists and is configured with a value of "1", this is a finding. Registry Hive: HKEY_CURRENT_USER Registry Path: \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Attachments\ Value Name: SaveZoneInformation Value Type: REG_DWORD Value: 0x00000002 (2) (or if the Value Name does not exist)

Check Text ( C-72015r2_chk )

The default behavior is for Windows to mark file attachments with their zone information.

If the registry Value Name below does not exist, this is not a finding.

If it exists and is configured with a value of "2", this is not a finding.

If it exists and is configured with a value of "1", this is a finding.

Registry Hive: HKEY_CURRENT_USER
Registry Path: \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Attachments\

Value Name: SaveZoneInformation

Value Type: REG_DWORD
Value: 0x00000002 (2) (or if the Value Name does not exist)

Fix Text (F-78717r1_fix)
The default behavior is for Windows to mark file attachments with their zone information. If this needs to be corrected, configure the policy value for User Configuration >> Administrative Templates >> Windows Components >> Attachment Manager >> "Do not preserve zone information in file attachments" to "Not Configured" or "Disabled".