← Back to Microsoft Outlook 2016 Security Technical Implementation Guide

V-228470

CAT II (Medium)

Internet calendar integration in Outlook must be disabled.

Rule ID

SV-228470r960963_rule

STIG

Microsoft Outlook 2016 Security Technical Implementation Guide

Version

V2R4

CCIs

CCI-000381

Discussion

This policy setting allows the user to determine whether or not to include Internet Calendar integration in Outlook. The Internet Calendar feature in Outlook enables users to publish calendars online (using the webcal:// protocol) and subscribe to calendars that others have published. When users subscribe to an internet calendar, Outlook queries the calendar at regular intervals and downloads any changes as they are posted. If this policy setting is enabled, all internet calendar functionality in Outlook is disabled. If this policy setting is disabled or not configured, Outlook allows users to subscribe to trusted and untrusted internet calendars. The webcal protocol also has a history of loading web sites vulnerable to cross site scripting.

Check Content

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Account Settings >> Internet Calendars "Do not include Internet Calendar integration in Outlook" is set to "Enabled".

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

HKCU\Software\Policies\Microsoft\Office\16.0\outlook\options\webcal

Criteria: If the value Disable is REG_DWORD = 1, this is not a finding.

Fix Text

Set the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Account Settings >> Internet Calendars "Do not include Internet Calendar integration in Outlook" to "Enabled".