2.5.14.3.31 (L1) Ensure 'Use Unicode format when dragging e-mail message to file system' is set to 'Disabled'

Information

This policy setting controls whether e-mail messages dragged from Outlook to the file system are saved in Unicode or ANSI format.

The recommended state for this setting is: Disabled

Unicode text is vulnerable to homograph attacks, in which characters are replaced by different but similar-looking characters. For example, the Cyrillic letter ? (U+0430) appears identical to the Latin letter a (U+0061) in many typefaces, but is actually a different character. Homographs can be used in 'phishing' attacks to convince victims to visit fraudulent Web sites and enter sensitive information.

Solution

To establish the recommended state via configuration profiles, set the following Settings Catalog path to Disabled :

Microsoft Outlook 2016\Security\Security Form Settings\Outlook Security Mode > Use Unicode format when dragging e-mail message to file system

Important: For this setting to apply, the

Outlook Security Mode

setting must be enabled in

Microsoft Outlook 2016\Security\Security Form Settings

with Use Outlook Security Group Policy selected, as set in this benchmark.

Impact:

ANSI file encoding may limit the overall size a .msg file can reach, although a single mail item should not be of concern.

See Also

https://workbench.cisecurity.org/benchmarks/15808

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6b.

Plugin: Windows

Control ID: ba2282821f8a7603e046849181b9d57a5a97bd1c7775d98a666135290defd054