Title

Users customizing attachment security settings must be prevented. (Cat II impact)

Discussion

All installed trusted COM addins can be trusted. Exchange settings for the addins still override if present and this option is selected.

Check Content

Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Security "Prevent users from customizing attachment security settings" is set to "Enabled". Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\15.0\outlook Criteria: If the value DisallowAttachmentCustomization is REG_DWORD = 1, this is not a finding.

Fix Text

Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Security "Prevent users from customizing attachment security settings" to "Enabled".

Additional Identifiers

Rule ID: SV-53929r1_rule

Vulnerability ID: V-17766

Group Title: DTOO238 - Prev't users customizing security set

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.