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This security update resolves vulnerabilities in Microsoft Skype for Business Server. To learn more about these vulnerabilities, see the following security advisories:

Note To apply this security update, you must have the release version of the following products installed:

  • Microsoft Skype for Business Server 2019

  • Microsoft Skype for Business Server 2015

Known issues in this update

In Skype for Business 2019 and 2015, the Debug-CsIntraPoolReplication cmdlet fails if you use the ConnectionUri parameter during a remote PowerShell session that was created by using an OcsPowerShell endpoint. For more information, see Debug-CsIntraPoolReplication fails using ConnectionUri in remote PowerShell with OcsPowerShell endpoint (KB5032556).

How to get and install the update

To get this update, install the following updates:

More information

Security update deployment information

For deployment information about this update, see Deployments - Security Update Guide.

How to get help and support for this security update

Protect yourself online: Windows Security support

Learn how we guard against cyber threats: Microsoft Security

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