Automatic download of Internet Calendar appointment attachments must be disallowed.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-17738	DTOO284	SV-54057r1_rule		Medium

Description
Files attached to Internet Calendar appointments could contain malicious code that could be used to compromise a computer. By default, Outlook does not download attachments when retrieving Internet Calendar appointments.

STIG	Date
Microsoft Outlook 2013 STIG	2018-09-05

Details

Check Text ( C-47997r1_chk )
Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Account Settings -> Internet Calendars "Automatically download attachments" 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\webcal Criteria: If the value EnableAttachments is REG_DWORD = 0, this is not a finding.

Check Text ( C-47997r1_chk )

Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Account Settings -> Internet Calendars "Automatically download attachments" 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\webcal

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

Fix Text (F-46937r1_fix)
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2013 -> Account Settings -> Internet Calendars "Automatically download attachments" to "Disabled".