Recipients of sent email must be unable to be added to the safe sender's list.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-17558	DTOO224 - Outlook	SV-33520r1_rule	ECSC-1	Medium

Description
Users could send e-mail messages to request that they be taken off a mailing list. If the e-mail recipient is then automatically added to the Safe Senders List, future e mail messages from that address will no longer be sent to the users Junk E-mail folder, even if it would otherwise be considered junk. By default, recipients of outgoing messages are not added automatically to individual users' Safe Senders Lists. However, users can change this configuration in the Outlook user interface.

Description

Users could send e-mail messages to request that they be taken off a mailing list. If the e-mail recipient is then automatically added to the Safe Senders List, future e mail messages from that address will no longer be sent to the users Junk E-mail folder, even if it would otherwise be considered junk. By default, recipients of outgoing messages are not added automatically to individual users' Safe Senders Lists. However, users can change this configuration in the Outlook user interface.

STIG	Date
Microsoft Outlook 2010	2015-09-17

Details

Check Text ( C-34007r1_chk )
The policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2010 -> Outlook Options -> Preferences -> Junk E-mail “Add e-mail recipients to users' Safe Senders Lists” must be set to “Disabled”. 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 JunkMailTrustOutgoingRecipients is REG_DWORD = 0, this is not a finding.

Check Text ( C-34007r1_chk )

The policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2010 -> Outlook Options -> Preferences -> Junk E-mail “Add e-mail recipients to users' Safe Senders Lists” must be set to “Disabled”.

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 JunkMailTrustOutgoingRecipients is REG_DWORD = 0, this is not a finding.

Fix Text (F-29695r1_fix)
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2010 -> Outlook Options -> Preferences -> Junk E-mail “Add e-mail recipients to users' Safe Senders Lists” to “Disabled”.