Applies To
Exchange Server 2019

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

Note: To mitigate the vulnerability, follow the instructions in the CVE bulletin.

Exchange Server Health Checker 

To verify that that the installation is successful, and check whether any additional actions are required, run the Exchange Server Exchange Server Health Checker.

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

Important: 

  • Organizations that are enrolled in the Extended Security Update (ESU) ​​​​​​​program are eligible to receive the February 2026 security updates and all subsequent updates for Exchange Server 2016 and 2019.

  • To continue receiving the latest security updates, organizations that aren't enrolled in the ESU program should migrate to Exchange Server Subscription Edition (SE).

  • If you have already purchased the ESU and require information about how to access the latest security updates, please email us at ExchangeandSfBServerESUInquiry@service.microsoft.com.

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 14 SU10

Exchange2019-KB5074994-x64-en.exe

CA2EC88B265C82E5D265B9A82A201CCEFA1D9F61D457508D388AB7A5698D40BC

Hashes for additional languages

The hash tables for additional languages are available here:

Exchange Server file information

The English (United States) version of this update installs files that have the attributes that are listed in the following tables. The dates and times for these files are listed in Coordinated Universal Time (UTC). The dates and times for these files on your local computer are displayed in your local time together with your current daylight-saving time (DST) bias. Additionally, the dates and times may change when you perform certain operations on the files.

Information about protection and security

Protect yourself online: Windows Security support

Learn how we guard against cyber threats: Microsoft Security

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