Sign in with Microsoft
Sign in or create an account.
Select a different account.
You have multiple accounts
Choose the account you want to sign in with.


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:

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This update is superseded by version 2 of the security update for Microsoft Exchange Server 2019 and 2016.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



Exchange Server 2019 Cumulative Update 12 SU9



Exchange Server 2016 Cumulative Update 23 SU9



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

Need more help?

Want more options?

Explore subscription benefits, browse training courses, learn how to secure your device, and more.

Communities help you ask and answer questions, give feedback, and hear from experts with rich knowledge.

Was this information helpful?

What affected your experience?
By pressing submit, your feedback will be used to improve Microsoft products and services. Your IT admin will be able to collect this data. Privacy Statement.

Thank you for your feedback!