Title

Windows Server 2019 must preserve zone information when saving attachments. (Cat II impact)

Discussion

Attachments from outside sources may contain malicious code. Preserving zone of origin (Internet, intranet, local, restricted) information on file attachments allows Windows to determine risk.

Check Content

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

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".

Additional Identifiers

Rule ID: SV-205924r569188_rule

Vulnerability ID: V-205924

Group Title: SRG-OS-000480-GPOS-00227

Expert Comments

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