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← Back to Microsoft Office 365 ProPlus Security Technical Implementation Guide

V-223344

CAT II (Medium)

The SIP security mode in Lync must be enabled.

Rule ID

SV-223344r1043178_rule

STIG

Microsoft Office 365 ProPlus Security Technical Implementation Guide

Version

V3R5

CCIs

CCI-001184

Discussion

When Lync connects to the server, it supports various authentication mechanisms. This policy allows the user to specify whether Digest and Basic authentication are supported. Disabled (default): NTLM/Kerberos/TLS-DSK/Digest/Basic Enabled: Authentication mechanisms: NTLM/Kerberos/TLS-DSK Gal Download: Requires HTTPS if user is not logged in as an internal user.

Check Content

Verify the policy value for Computer Configuration >> Administrative Templates >> Skype for Business 2016 >> Microsoft Lync Feature Policies "Configure SIP security mode" 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 enablesiphighsecuritymode is REG_DWORD = 1, this is not a finding.

Fix Text

Set the policy value for Computer Configuration >> Administrative Templates >> Skype for Business 2016 >> Microsoft Lync Feature Policies "Configure SIP security mode" to "Enabled".