Applies ToExchange Server 2019 Exchange Server 2016

Notice

We have re-released the Exchange Server 2019 and 2016 August 8, 2023, security update (SU) to address the localization issue that caused installations on non-English operating systems (OS) to fail. You can find the re-released version of the SU here:

   https://support.microsoft.com/help/5030524

The SU will also soon be available through Microsoft Update / Windows Update. For more information about the re-release, see this Exchange Team Blog article.

Original article content

This security update rollup resolves vulnerabilities in Microsoft Exchange Server. To learn more about these vulnerabilities, see the following Common Vulnerabilities and Exposures (CVE)

Issues that are fixed in this update

Features introduced in this update 

Known issues in this update

Enabling Extended Protection in Exchange Server

To enable Extended Protection on Exchange-based servers, see Extended Protection enabled in Exchange Server (KB5017260).

How to get and install the update

This update is superseded by version 2 of the security update for Microsoft Exchange Server 2019 and 2016. For more information, see the "Known issues in this update" section in this article.

More information

Security update deployment information

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

Security update replacement information

This security update replaces the following previously released updates:

File information

File hash information

Update Name

File name

SHA256 hash

Exchange Server 2019 Cumulative Update 13 SU2

Exchange2019-KB5029388-x64-en.exe

AB47764A566A5555474BFF3AB3FDE03DC47C5E31B35B6BA196E25D9FBBD7DA48

Exchange Server 2019 Cumulative Update 12 SU9

Exchange2019-KB5029388-x64-en.exe

5539D00A4721AFF37AD804AA899B267D0F480039015745C15265D998D0338B18

Exchange Server 2016 Cumulative Update 23 SU9

Exchange2016-KB5029388-x64-en.exe

622C0D5441E1484A5FD5BE7438689E1D7722542A4B93ECF1A108214A9346C678

Hashes for additional languages

The hash tables for additional languages are available here:

Information about protection and security

Protect yourself online: Windows Security support

Learn how we guard against cyber threats: Microsoft Security

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