KB5025808 Cumulative Update 21 for SQL Server 2019

KB5025808 is a cumulative update for SQL Server 2019. It was released on 15th January 2023 to address the various security vulnerabilities on the database server.

We look at the details of KB5025808 below.

Topics covered in this post

Salient points about KB5025808

KB5025808 is the cumulative update 21 for SQL Server 2019. It supersedes the Cumulative update 20 for SQL Server 2019.
Cumulative Update 20 for Microsoft SQL Server 2019 was released on 13th April 2023. KB5024276 is the CU 20 for SQL Server.
KB5024276 corresponds to SQL Server 2019 version 15.0.4312.2.
KB5025808 corresponds to SQL Server 2019 version 15.0.4316.3.
KB5025808 addresses 28 bugs or issues on SQL Server 2019. A full list of bugs that have been resolved can be found in the release notes for KB5025808 on the Microsoft website.
KB5025808 also resolves a couple of Known issues on SQL Server 2019. These issues are discussed in brief below.
KB5025808 is cumulative in nature and contains all changes that are part of the previous Cumulative Updates.
Upon application of KB5025808 on the server, the server will reboot. So, please plan the change as part of a maintenance window.
KB5025808 is available for SQL Server 2019 running on Windows Server 2022, Windows Server 2019, Windows Server 2018, Windows 11, and Windows 10.
On a similar note, KB5025808 is also available for Linux servers and Big Data Clusters.
We strongly suggest taking a backup of the database before attempting an installation of KB5025808 on SQL Server 2019.

Download KB5025808 for Windows

You can download the updated file for KB5025808 from the Microsoft site. The file is available as an executable file with a .exe extension (size is 751 MB). The download resources for KB5025808 for the Windows platform are shared below.

KB5025808 can be downloaded from the Microsoft Download Center,
Microsoft Update Catalog, or
through a direct download link for the executable file.

Cumulative Update 21 for Microsoft SQL Server 2019 has a file size of 751 MB. The download resources are published below.

KB5025808 platforms	Download link	Direct Download link
Windows Server 2016, Windows Server 2019, Windows Server 2022	Download KB5025808 from Microsoft Download Center	Direct download KB5025808 from Microsoft Download Center
Windows Server 2016, Windows Server 2019, Windows Server 2022	Microsoft Update Catalog	Direct download of KB5025808 from Microsoft Update Catalog

Download KB5025808 for Linux

SQL Server 2019 on Linux needs to be configured on the server using the repository. Once SQL Server is deployed on Linux, you can use the standard Linux commands to update the package on the server.

SQL Server package mssql-server will get updated to the latest package after you run these commands below for SQL Server 2019 Cumulative Update 21:

Red Hat Enterprise Linux (RHEL)

Use the following command to fetch the latest Sql Server package:

sudo yum update mssql-server

SUSE Linux Enterprise Server (SLES)

Use the following command to fetch the latest Sql Server package:

sudo zypper update mssql-server

Ubuntu

Update SQL Server 2019 Cumualtive Update 21 for Ubuntu using the following command:

sudo apt-get update
sudo apt-get install mssql-server

When you execute these commands in the Linux shell, the binaries under /opt/mssql/ will get updated with the binaries that are part of the latest Cumulative Update 21 for SQL Server 2019.

SQL Server builds and SQL Server Files

Each SQL Server upgrade results in a unique SQL Server build version. For each SQL Server build version, you also get a unique Sqlservr.exe file version.

The table below lists the last 3 SQL Server 2019 builds and Sqlservr file versions that correspond to the build.

SQL Server 2019 Cumulative Update	Build version	Sqlservr.exe version
KB5025808	15.0.4316.3	2019.150.4316.3
KB5024276	15.0.4312.2	2019.150.4312.2
KB5023049	15.0.4298.1	2019.150.4298.1

Cumulative updates for Windows Servers

It is always a good idea to upgrade the underlying servers before attempting an upgrade of the SQL Server package to Cumulative Update 21.

On June 13, 2023, Microsoft released cumulative updates for Windows Servers under the ‘Patch Tuesday’ project. For your ready reference, the cumulative updates for Windows Server 2022, Windows Server 2019, and Windows Server 2016 are discussed in the documents below.

Once the servers have been updated to the latest build, you can proceed with the installation of latest SQL Server package CU 21 for SQL Server 2019.

About Cumulative Updates and Hotfixes for SQL Server

The cumulative updates for SQL Server are different than the Release to Manufacturing (RTM) packages.

A cumulative update is a roll-up update that contains all previous critical on-demand hotfixes to date. Additionally, a CU contains fixes for issues that meet the hotfix acceptance criteria. These criteria may include the availability of a workaround, the effect on the customer, the reproducibility of the problem, the complexity of the code that must be changed, and other topics.

So a cumulative update is a collection of hotfix files.

In the case of Cumulative Update 21 for Microsoft SQL Server 2019, we have 2 issue resolutions and 28 bug fixes.

A Hotfix is a special package that is created to address a single issue. It is an emergency fix for an issue that could pose a critical threat or impact on the working of SQL Server 2019.

A hotfix is a single, cumulative package that includes one or more files that are used to address a problem in a product and are cumulative at the binary and file level. A hotfix addresses a specific customer situation and may not be distributed outside the customer’s organization.

June 2023 Cumulative Updates

The following security or cumulative updates have been released in June 2023:

Rajesh Dhawan

Rajesh Dhawan is a technology professional who loves to blog about smart wearables, Cloud computing and Microsoft technologies. He loves to break complex problems into manageable chunks of meaningful information.