Read signed email as plain text must be enforced.
An XCCDF Rule
Description
<VulnDiscussion>Outlook can display email messages and other items in three formats: plain text, Rich Text Format (RTF), and HTML. By default, Outlook displays digitally signed email messages in the format they were received in.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility>System Administrator</Responsibility><Responsibility>Information Assurance Officer</Responsibility><IAControls></IAControls>
- ID
- SV-53868r1_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Outlook Options -> Preferences -> E-mail Options "Read signed e-mail as plain text" to "Enabled".