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V-223353

CAT II (Medium)

Outlook must be configured to prevent users overriding attachment security settings.

Rule ID

SV-223353r961353_rule

STIG

Microsoft Office 365 ProPlus Security Technical Implementation Guide

Version

V3R5

CCIs

CCI-002235

Discussion

This policy setting prevents users from overriding the set of attachments blocked by Outlook. If you enable this policy setting users will be prevented from overriding the set of attachments blocked by Outlook. Outlook also checks the "Level1Remove" registry key when this setting is specified. If you disable or do not configure this policy setting, users will be allowed to override the set of attachments blocked by Outlook.

Check Content

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Security >> Prevent users from customizing attachment security settings is set to "Enabled".

Use the Windows Registry to navigate to the following key:

HKCU\software\policies\microsoft\office\16.0\outlook

If the value for disallowattachmentcustomization is set to REG_DWORD = 1, this is not a finding.

Fix Text

Set the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Security >> Prevent users from customizing attachment security settings to "Enabled".