Detections
Analytics
5.1.8 Set 'Do not prompt about Level 1 attachments when sending an item' to 'Disabled'
Information
This policy setting controls whether Outlook displays a warning before sending an itemthat contains an unsafe attachment that will be blocked when the item is opened by a
recipient. To protect users from viruses and other harmful files, Outlook uses two levels of
security, designated Level 1 and Level 2, to restrict access to files attached to e-mail
messages or other items. Outlook completely blocks access to Level 1 files by default, and
requires users to save Level 2 files to disk before opening them. Potentially harmful files
can be classified into these two levels by file type extension, with all other file types
considered safe. If you enable this policy setting, Outlook will not display a warning when a
user sends an item with a Level 1 attachment, which can cause users' data to be at risk. If
you disable or do not configure this policy setting, when users attempt to send an item to
which a level 1 file has been attached, Outlook warns them that the message contains a
potentially unsafe attachment and that the recipient might not be able to access it.
Important- This policy setting only applies if the 'Outlook Security Mode' policy setting
under 'Microsoft Outlook 2010\Security\Security Form Settings' is configured to 'Use
Outlook Security Group Policy.' The recommended state for this setting is- Disabled.
*Rationale*
To protect users from viruses and other harmful files, Outlook 2010 uses two levels of
security, designated Level 1 and Level 2, to restrict access to files attached to e-mail
messages or other items. Outlook completely blocks access to Level 1 files by default, and
requires users to save Level 2 files to disk before opening them. Potentially harmful files
can be classified into these two levels by file type extension, with all other file types
considered safe. By default, when users attempt to send an item to which a level 1 file has
been attached, Outlook warns them that the message contains a potentially unsafe
attachment and that the recipient might not be able to access it. If this configuration is
changed, Outlook will not display the warning when users send such items, which can
cause users to lose access to important data.
Solution
To implement the recommended configuration state, set the following Group Policy settingto Disabled.
User Configuration\Administrative Templates\Microsoft Outlook 2010\Security\Security
Form Settings\Attachment Security\Do not prompt about Level 1 attachments when sending
an item
Impact-Disabling this setting enforces the default configuration in Outlook 2010, and therefore is
unlikely to cause usability issues for most users. Important For this setting to apply, you
must also enable the 'Outlook Security Mode' setting in
User Configuration\Administrative
Templates\Classic Administrative Templates (ADM)\Microsoft Office Outlook
2010\Security\Security Form Settings\Microsoft Office Outlook 2010 Security and select
Use Outlook Security Group Policy from the drop-down list.
See Also
Item Details
Audit Name: CIS MS Office Outlook 2010 v1.0.0
Category: CONFIGURATION MANAGEMENT
References: 800-53|CM-6b.
Plugin: Windows
Control ID: 62a2e166f5ba3070a14efe61a627beeb967354f08ada3036ba317aea691d783e