Missing Root Certificates warning must be enforced.
An XCCDF Rule
Description
<VulnDiscussion>When Outlook accesses a certificate, it validates that it can trust the certificate by examining the root certificate of the issuing CA. If the root certificate can be trusted, then certificates issued by the CA can also be trusted. If Outlook cannot find the root certificate, it cannot validate that any certificates issued by that CA can be trusted. An attacker may compromise a root certificate and then remove the certificate in an attempt to conceal the attack. By default, Outlook displays a warning message when a CRL is not available.</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-54033r1_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Security -> Cryptography -> Signature Status dialog box "Missing root certificates" to "Enabled (Error)".