The HTTP fallback for SIP connection in Lync must be disabled.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
|---|---|---|---|---|
| V-99765 | O365-LY-000002 | SV-108869r1_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 | 2020-06-17 |
Details
| Check Text ( C-98615r1_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-105449r1_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". |