Recipients of sent email must be unable to be added to the safe senders list.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-17558	DTOO224	SV-53885r1_rule		Medium

Description
Users could send email messages to request that they be taken off a mailing list. If the email 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 email 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 email messages to request that they be taken off a mailing list. If the email 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 email 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 2013 STIG	2018-09-05

Details

Check Text ( C-47917r1_chk )
Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Outlook Options -> Preferences -> Junk E-mail "Add e-mail recipients to users' Safe Senders Lists" is set to "Disabled". Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\15.0\outlook\options\mail Criteria: If the value JunkMailTrustOutgoingRecipients is REG_DWORD = 0, this is not a finding.

Check Text ( C-47917r1_chk )

Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Outlook Options -> Preferences -> Junk E-mail "Add e-mail recipients to users' Safe Senders Lists" is set to "Disabled".

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

HKCU\Software\Policies\Microsoft\Office\15.0\outlook\options\mail

Criteria: If the value JunkMailTrustOutgoingRecipients is REG_DWORD = 0, this is not a finding.

Fix Text (F-46790r1_fix)
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Outlook Options -> Preferences -> Junk E-mail "Add e-mail recipients to users' Safe Senders Lists" to "Disabled".