Display Level 1 attachments

Information

This policy setting controls whether Outlook blocks potentially dangerous attachments designated Level 1. Outlook uses two levels of security to restrict users' access to files attached to e-mail messages or other items. Files with specific extensions can be categorized as Level 1 (users cannot view the file) or Level 2 (users can open the file after saving it to disk). Users can freely open files of types that are not categorized as Level 1 or Level 2.

If you enable this policy setting Outlook users can gain access to Level 1 file type attachments by first saving the attachments to disk and then opening them as with Level 2 attachments. If you disable this policy setting Level 1 attachments do not display under any circumstances. If you do not configure this policy setting Outlook completely blocks access to Level 1 files and requires users to save Level 2 files to disk before opening them.

Solution

Policy Path: Microsoft Outlook 2016\Security\Security Form Settings\Attachment Security
Policy Setting Name: Display Level 1 attachments

See Also

https://blogs.technet.microsoft.com/secguide/2018/02/13/security-baseline-for-office-2016-and-office-365-proplus-apps-final/

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-18(4)

Plugin: Windows

Control ID: 228207e93486090563f5aa38bea6435c6a784241a259eb02bb4b2a9f9a768c63