Warning about invalid signatures must be enforced.
An XCCDF Rule
Description
If users open e-mail messages that include invalid digital signatures, Outlook displays a warning dialog box. Users can decide whether they want to be warned about invalid signatures in the future. If users are not notified about invalid signatures, they might be prevented from detecting a fraudulent signature sent by a malicious person.
| Property | Value |
|---|---|
| Responsibility | System Administrator |
- ID
- SV-33571r1_rule
- Version
- DTOO265 - Outlook
- Severity
- Medium
- References
- Updated
Remediation Templates
A Manual Procedure
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2010 -> Security -> Cryptography “Signature Warning” to “Enabled (Always warn about invalid signatures)”.