UCF STIG Viewer Logo
Changes are coming to https://stigviewer.com. Take our survey to help us understand your usage and how we can better serve you in the future.
Take Survey

The HTTP fallback for SIP connection in Lync must be disabled.


Overview

Finding ID Version Rule ID IA Controls Severity
V-223345 O365-LY-000002 SV-223345r879636_rule Medium
Description
Prevents from HTTP being used for SIP connection in case TLS or TCP fail.
STIG Date
Microsoft Office 365 ProPlus Security Technical Implementation Guide 2024-02-21

Details

Check Text ( C-25018r442254_chk )
Verify the policy value for Computer Configuration >> Administrative Templates >> Skype for Business 2016 >> Microsoft Lync Feature Policies "Disable HTTP fallback for SIP connection" is set to "Enabled".

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

HKLM\Software\Policies\Microsoft\office\16.0\lync

If the value disablehttpconnect is REG_DWORD = 1, this is not a finding.
Fix Text (F-25006r442255_fix)
Set the policy value for Computer Configuration >> Administrative Templates >> Skype for Business 2016 >> Microsoft Lync Feature Policies "Disable HTTP fallback for SIP connection" to "Enabled".