Read signed email as plain text must be enforced.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-17771	DTOO215 - Outlook	SV-33519r1_rule	ECSC-1	Medium

Description
Outlook can display e-mail messages and other items in three formats: plain text, Rich Text Format (RTF), and HTML. By default, Outlook displays digitally signed e-mail messages in the format they were received in.

STIG	Date
Microsoft Outlook 2010	2014-10-03

Details

Check Text ( C-34006r1_chk )
The policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2010 -> Outlook Options -> Preferences -> E-mail Options “Read signed e-mail as plain text” must be set to “Enabled”. Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\14.0\outlook\options\mail Criteria: If the value ReadSignedAsPlain is REG_DWORD = 1, this is not a finding.

Check Text ( C-34006r1_chk )

The policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2010 -> Outlook Options -> Preferences -> E-mail Options “Read signed e-mail as plain text” must be set to “Enabled”.

Procedure: Use the Windows Registry Editor to navigate to the following key:

HKCU\Software\Policies\Microsoft\Office\14.0\outlook\options\mail

Criteria: If the value ReadSignedAsPlain is REG_DWORD = 1, this is not a finding.

Fix Text (F-29694r1_fix)
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2010 -> Outlook Options -> Preferences -> E-mail Options “Read signed e-mail as plain text” to “Enabled”.