The HTTP fallback for SIP connection in Lync must be disabled.
An XCCDF Rule
Description
<VulnDiscussion>Prevents from HTTP being used for SIP connection in case TLS or TCP fail.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-223345r961110_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
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".