Description of the security update for Skype for Business Server and Lync Server: May 11, 2021 (KB5003729)

Summary

This security update resolves vulnerabilities in Microsoft Skype for Business Server and Microsoft Lync Server. To learn more about these vulnerabilities, see Microsoft Common Vulnerabilities and Exposures CVE-2021-26422 and Microsoft Common Vulnerabilities and Exposures CVE-2021-26421.

Improvements and fixes

This update also fixes the following issue:Remote PowerShell cannot be connected after you install update 4470124 for Skype for Business 2019.

How to get and install the update

To get this update, install the following updates:

• Update for Skype for Business Server 2019
• Update for Skype for Business Server 2015
• Update for Lync Server 2013

More information

Security update deployment information

For deployment information about this update, see security update deployment information: May 11, 2021.

How to get help and support for this security update

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