Detections
Analytics
5.1.10 Set 'Configure Outlook object model prompt when sending mail: Guard behavior:' to 'Enabled:Automatically Deny'
Information
This policy setting controls what happens when an untrusted program attempts to send e-mail programmatically using the Outlook object model.
If you enable this policy setting, you can choose from four different options when an
untrusted program attempts to send e-mail programmatically using the Outlook object
model-. Prompt user - The user will be prompted to approve every access attempt.
. Automatically approve - Outlook will automatically grant programmatic access
requests from any program. This option can create a significant vulnerability, and is
not recommended.
. Automatically deny - Outlook will automatically deny programmatic access requests
from any program.
. Prompt user based on computer security. Outlook will only prompt users when
antivirus software is out of date or not running.
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.'
If you disable or do not configure this policy setting, when an untrusted application
attempts to send mail programmatically, Outlook relies on the setting configured in the
'Programmatic Access' section of the Trust Center. This setting determines whether
Outlook will warn users about programmatic access attempts-
. Only when antivirus software is out of date or not running (the default setting)
. Every time
. Not at all - If the 'Not at all' option is selected, Outlook will silently grant
programmatic access to any program that requests it.Note- This described default functionality assumes that you have not followed the
recommendation to enable the 'Outlook Security Mode' Group Policy setting to ensure that
Outlook security settings are configured by Group Policy. If Group Policy security settings
are used for Outlook, the 'Programmatic Access' section of the Trust Center is not used. In
this situation, the default is to prompt users based on computer security, which is the
equivalent of the 'Only when antivirus software is out of date or not running' option in the
Trust Center, and the user experience is not affected.
For more information about the Object Model Guard, see Security Behavior of Outlook
(http-//officeredir.microsoft.com/r/rlidGPSecBehaviorOutlookModelO14?clid=1033) in
the MSDN Outlook 2010 Developer Reference. The recommended state for this setting is-
Enabled-Automatically Deny.
*Rationale*
If an untrusted application programmatically sends e-mail, that application could send mail
that includes malicious code, impersonate a user, or launch a denial-of-service attack by
sending a large volume of mail to a user or group of users.
By default, when an untrusted application attempts to send mail programmatically, Outlook
2010 relies on the setting configured in the 'Programmatic Access' section of the Trust
Center. This setting determines whether Outlook will warn users about programmatic
access attempts-. Only when antivirus software is out of date or not running (the default setting)
. Every time
. Not at allIf the 'Not at all' option is selected, Outlook will silently grant programmatic access to any
program that requests it, which could allow a malicious program to gain access to sensitive
information.
Note- This described default functionality assumes that you have not followed the
recommendation to enable the 'Outlook Security Mode' Group Policy setting to ensure that
Outlook security settings are configured by Group Policy. If Group Policy security settings
are used for Outlook, the 'Programmatic Access' section of the Trust Center is not used. In
this situation, the default is to prompt users based on computer security, which is the
equivalent of the 'Only when antivirus software is out of date or not running' option in the
Trust Center, and the user experience is not affected.
Solution
To implement the recommended configuration state, set the following Group Policy settingto Enabled.
User Configuration\Administrative Templates\Microsoft Outlook 2010\Security\Security
Form Settings\Programmatic Security\Configure Outlook object model prompt when sending
mail\Configure Outlook object model prompt when sending mail
Then set the Configure Outlook object model prompt when sending mail- Guard
behavior- option to Automatically Deny.
Impact-Enabling this setting and selecting Prompt user based on computer security enforces the
default configuration in Outlook 2010, and therefore is unlikely to cause usability issues for
most users.Important- If this setting is enabled, 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.For more information about the Object Model Guard, see Security Behavior of the Outlook
Object Model in the MSDN Outlook Developer Reference.
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: ec4b3fccef34c8ff215bcad688da0ee84df73f339637f6327c9fc05cd9fab246