KB5125471 - Cumulative Update 10 for SQL Server 2025

Release Date:   October 22, 2026
Version:   17.0.5035.5

Summary

This article describes Cumulative Update 10 (CU10) for Microsoft SQL Server 2025. This update package contains 36 fixes that were issued after the release of SQL Server 2025 Cumulative Update 9. It updates components in the following builds:

  • SQL Server - Product version: 17.0.5035.5, file version: 2025.170.5035.5
  • Analysis Services - Product version: 17.0.25.223, file version: 2025.170.25.223

Important

To help secure SQL Server on Windows, enable encryption with Extended Protection.

Known issues in this update

Incorrect behavior of SESSION_CONTEXT in parallel plans

Queries that use the built-in SESSION_CONTEXT function might return incorrect results or trigger access violation (AV) dump files when run in parallel query plans. This issue occurs because of the manner in which SESSION_CONTEXT interacts with parallel execution threads, particularly if the session is reset for reuse.

For more information, see the Known issues section in SESSION_CONTEXT.

Access violation when you query sys.dm_exec_requests during database recovery

Queries against sys.dm_exec_requests might raise an access violation and generate a dump file if they run while a database is still recovering. This issue can occur during a database RESTORE operation, during startup recovery, or before an availability group replica finishes coming online.

The SQL Server error log contains entries that resemble the following text:

The database '<DatabaseName>' is marked RESTORING and is in a state that does not allow recovery to be run.
***Stack Dump being sent to <SQLServerLogFolder>\SQLDump0215.txt
SqlDumpExceptionHandler: Process 77 generated fatal exception c0000005 EXCEPTION_ACCESS_VIOLATION. SQL Server is terminating this process.
*******************************************************************************

BEGIN STACK DUMP:
  07/30/26 07:37:23 spid 77

Exception Address = <frame id="00" address="0x7FFDED94970D" pdb="sqlmin.pdb" age="2" guid="E1039014-237E-4DB6-88FD-4A2AB31C651F" module="sqlmin" rva="0x2970D" />
Exception Code    = c0000005 EXCEPTION_ACCESS_VIOLATION
Access Violation occurred reading address 00000000000000F0
Input Buffer <size> bytes -
          <dbo.sp_YourMonitoringStoredProcedure>

This issue occurs because of a change that causes internal in-memory structures to be referenced before they're fully initialized.

Microsoft is aware of this issue and is investigating a fix. Until a fix is available, use one of the following mitigations:

  • Enable trace flag 4696 to opt out of the code change that causes this issue. If you enable this trace flag, monitoring queries that query sys.dm_exec_requests or sys.sysprocesses on secondary replicas might return error 976 or error 978, as they did before you installed this update.
  • Avoid queries against sys.dm_exec_requests for databases that are recovering.
  • Uninstall this update.

Improvements and fixes included in this update

A downloadable Microsoft Excel workbook that contains a summary list of builds, together with their current support lifecycle, is available. The Excel file also contains detailed fix lists for SQL Server 2025, SQL Server 2022, SQL Server 2019, and SQL Server 2017. Download this Excel file now.

Note

Individual entries in the following table can be referenced directly through a bookmark. If you select any bug reference ID in the table, a bookmark tag is added to the URL by using the "#NNNNNNN" format. You can then share this URL with others so that they can jump directly to the desired fix in the table.

For more information about the bugs that are fixed and enhancements that are included in this cumulative update, see the following table.

Bug reference Description Fix area Component Platform
5090700 Fixes an issue in which a self-assignment update on a small off-row XML column that has XML compression enabled causes XML data corruption and a transport-level error when the data is selected. SQL Server Engine Methods to access stored data All
5318463 Fixes an issue in which creating a JSON index on a long JSON path that contains multibyte Unicode characters can cause SQL Server to end unexpectedly if the path exceeds 8,000 bytes after UTF-8 conversion. SQL Server Engine Programmability All
5419454 Fixes a security vulnerability in PolyBase by improving validation during data processing. SQL Server Engine PolyBase All
5439307 Fixes an issue in which the SQL Server process might end unexpectedly when it accesses external data sources. SQL Server Engine PolyBase All
5491072 Fixes an input validation issue in which malformed size values in Virtual Device Interface (VDI) and SQL Server VSS Writer backup operations can cause out-of-bounds memory access. SQL Server Engine Backup Restore Windows
5494339 Addresses an integer handling issue in SQL Server backup and restore metadata processing that potentially allows a local authenticated user to gain elevated privileges and cause a service to stop responding. SQL Server Engine Backup Restore Windows
5505572 Updates the third-party archive extraction component that SQL Server uses to install external language and external library packages. SQL Server Engine Extensibility All
5522142 Adds validation of FILESTREAM fragment sizes on availability group secondary replicas to reject oversized fragments. SQL Server Engine High Availability and Disaster Recovery All
5529171 Fixes improper field offset validation in the SqlDataRecord.SetBytes API for sql_variant values that can cause an out-of-bounds heap write action if CLR integration is turned on. SQL Server Engine Programmability Windows
5529204 Improves the handling of Showplan input to enhance security and reliability. SQL Server Engine Query Store Windows
5529345 Improves the protection of internal replication data during processing operations. SQL Server Engine Replication All
5529358 Improves the handling of text data in merge replication to enhance security and reliability. SQL Server Engine Replication All
5529370 Improves the validation and handling of replication operations to enhance security and reliability. SQL Server Engine Replication All
5529381 Improves the security and reliability of queued updating subscriptions in transactional replication. SQL Server Engine Replication Windows
5529395 Improves the security and reliability of queued updating subscriptions in transactional replication. SQL Server Engine Replication Windows
5529458 Fixes an issue in Change Event Streaming (CES) that prevents event deserialization if event data payloads contain certain characters. SQL Server Engine Replication All
5529462 Fixes SQL Server dump files that might occur during serialization of large object data that's streamed through Change Event Streaming. SQL Server Engine Replication All
5555143 Fixes an issue in which creating a contained availability group might fail and return an "1803" error message after a first-boot collation change on SQL Server on Linux. SQL Server Engine Linux Linux
5555768 Adds validation of Delta Lake table schema metadata. SQL Server Engine PolyBase All
5558665 Improves the handling of shared memory in PolyBase. SQL Server Engine PolyBase All
5571219 Fixes a security vulnerability in the SQL Server Virtual Device Interface (VDI) in which an out-of-bounds write action might occur when a virtual device set is opened. SQL Server Engine Backup Restore All
5571935 Fixes a security vulnerability in the SQL Server Virtual Device Interface (VDI) in which an out-of-bounds read or write action might occur when transferred data is processed during backup or restore operations. SQL Server Engine Backup Restore All
5574835 Fixes an invalid memory read vulnerability in the processing of runtime parameters for the AI_GENERATE_EMBEDDINGS function. SQL Server Engine Extensibility All
5575381 Fixes unsafe deserialization of PolyBase rollback queue data so that malformed payloads are rejected. SQL Server Engine PolyBase All
5578870 Fixes multiple memory corruption and memory disclosure vulnerabilities in the parsing of SQLSatellite protocol messages that Machine Learning Services and Language Extensions use. SQL Server Engine Extensibility All
5582011 Fixes an issue in which linked server connections that use the MSDASQL provider might fail if the provider string doesn't include a user ID (UID). SQL Server Engine Distributed Query All
5632692 Improves the security and reliability of replication security metadata handling during subscriber database restore and upgrade operations. SQL Server Engine Replication Windows
5632803 Improves the security and reliability of the Log Reader Agent in heterogeneous transactional replication scenarios. SQL Server Engine Replication Windows
5632816 Improves the security and reliability of the change feed configuration. SQL Server Engine Replication Windows
5632851 Fixes a buffer overflow that occurs when merge replication processes more than 250 XML nickname entries during web synchronization. SQL Server Engine Replication All
5632877 Fixes an issue in replication operations that affects data validation. SQL Server Engine Replication All
5632890 Fixes an issue that affects data validation in Web synchronization operations for merge replication. SQL Server Engine Replication All
5632903 Fixes an issue in the processing of input data for Change Event Streaming. SQL Server Engine Replication All
5632930 Improves the security of the sp_replcounters stored procedure. SQL Server Engine Replication Windows
5635187 Improves security validation for stored procedures that merge replication uses. SQL Server Engine Replication Windows
5635965 Fixes an issue in which malformed trace data can cause an out-of-bounds read action when SQL Trace processes the LoginSid column. SQL Server Engine Programmability All

How to obtain or download this CU or the latest CU package

How to obtain or download the latest cumulative update package for Windows (recommended)

The following update is available from the Microsoft Download Center:

Download the latest cumulative update package for SQL Server 2025 now

Note

  • Microsoft Download Center always offers the latest SQL Server 2025 CU release.
  • If the download page doesn't appear, contact Microsoft Customer Service and Support to obtain the cumulative update package.
How to obtain or download this cumulative update package for Windows from Microsoft Update Catalog

The following update is available from the Microsoft Update Catalog:

Note

  • Microsoft Update Catalog contains this SQL Server 2025 CU and previously released SQL Server 2025 CU releases.
  • This CU is also available through Windows Server Update Services (WSUS).
  • We recommend that you always install the latest cumulative update that's available.
How to obtain or download the latest cumulative update package for Linux

To update SQL Server 2025 on Linux to the latest CU, you must first have the Cumulative Update repository configured. Then, update your SQL Server packages by using the appropriate platform-specific update command.

For installation instructions and direct links to the CU package downloads, see the SQL Server 2025 Release Notes.

File information

File hash information

You can verify the download by computing the hash of the SQLServer2025-KB5125471-x64.exe file through the following command:

certutil -hashfile SQLServer2025-KB5125471-x64.exe SHA256

File name SHA256 hash
SQLServer2025-KB5125471-x64.exe EBDC3024C76023CE599D3FDF3174A1FC8FF2958EE7009A7655274CE263644B85
Cumulative Update package file information

Download the list of files that are included in KB5125471.

Notes for this update

Prerequisites

To apply this cumulative update package, you must be running SQL Server 2025.

Restart information

You might have to restart the computer after you apply this cumulative update package.

Registry information

To use one of the hotfixes in this package, you don't have to make any changes to the registry.

Important notices

This article also provides the following important information.

Analysis Services CU build version

Beginning in Microsoft SQL Server 2017, the Analysis Services build version number and SQL Server Database Engine build version number don't match. For more information, see Verify Analysis Services cumulative update build version.

Cumulative updates (CU)

  • Each new CU contains all the fixes that were included in the previous CU for the installed version of SQL Server.
  • SQL Server CUs are certified to the same levels as service packs, and should be installed at the same level of confidence.
  • We recommend ongoing, proactive installation of CUs as they become available according to these guidelines:
    • Historical data shows that a significant number of support cases involve an issue that was already addressed in a released CU.
    • CUs might contain added value over and above hotfixes, such as supportability, manageability, and reliability updates.
  • We recommend that you test SQL Server CUs before you deploy them to production environments.
Hybrid environment deployment

When you deploy an update to a hybrid environment (such as Always On, replication, cluster, and mirroring), we recommend that you refer to the following articles before you deploy the update:

Language support

SQL Server CUs are currently multilingual. Therefore, this CU package isn't specific to one language. It applies to all supported languages.

Components (features) updated

One CU package includes all available updates for all SQL Server 2025 components (features). However, the cumulative update package updates only those components that are currently installed on the SQL Server instance that you select to be serviced. If a SQL Server feature (for example, Analysis Services) is added to the instance after this CU is applied, you must reapply this CU to update the new feature to this CU.

Support for this update

If other issues occur, or if any troubleshooting is required, you might have to create a service request. The usual support costs will apply to additional support questions and to issues that don't qualify for this specific cumulative update package. For a complete list of Microsoft Customer Service and Support telephone numbers, or to create a separate service request, go to the Microsoft support website.

How to uninstall this update

How to uninstall this update on Windows
  1. In Control Panel, open the Programs and Features item, and then select View installed updates.
  2. Locate the entry that corresponds to this cumulative update package under SQL Server 2025.
  3. Press and hold (or right-click) the entry, and then select Uninstall.
How to uninstall this update on Linux

To uninstall this CU on Linux, you must roll back the package to the previous version. For more information about how to roll back the installation, see Rollback SQL Server.

References