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SQL Server 2022 CU18 SQL Server 2022 CU18 Cumulative update

KB5050771

KB5050771: Cumulative update for SQL Server 2022, CU branch, March 2025. Contained availability groups gain instance-level workload groups

In short

CU18 adds 11 fixes for SQL Server 2022 and lets contained availability groups use instance-level Resource Governor workload groups. Queries using SESSION_CONTEXT might still return incorrect results or trigger access violation dumps in parallel plans.

Does it affect you? Applies to: SQL Server 2022 instances on Windows or Linux, in any supported language. The update refreshes the components installed on the instance; its Analysis Services build is 16.0.43.242.

Build
16.0.4185.3
Servicing branch
CU
Restart
Required
Review notes Additional details from the official release notes (2) Read notes
  • What changes DQS is supported only in Enterprise and Developer editions. This fix prevents installation in Standard or Web edition and applies to new installations only.
  • What to do KB5050771 has been superseded by KB5054531. Microsoft recommends installing the latest available cumulative update.

The official sources are linked at the end of the page.

For servers on the CU branch: they install cumulative updates, which also bring fixes beyond security. Servers on the GDR branch (security fixes only) get a separate update. Which branch am I on?

What changes

Fixes 10 changes

Backup Restore

For: SQL Server administrators using availability groups

  • A copy-only filegroup backup on an availability group secondary replica no longer fails with an unsupported-backup error.1
    Fixes errors 3059 and 3013 when running the backup.

Linux

2 items

For: SQL Server administrators on Linux

  • Some transactions no longer encounter extended waits during flush operations when the alternate write-through setting is enabled.2
    Fixes a race condition during flush operations when control.alternatewritethrough = 1.
  • Self-signed certificates created for SQL Server on Linux no longer might have a negative serial number.3

Management Services

  • Database Mail log messages containing non-ASCII characters no longer might appear as question marks.4
    Fixes values stored in the msdb database's sysmail_log system table and displayed in the sysmail_event_log view. The issue is more common on localized SQL Server versions, such as Japanese.

Metadata

For: SQL Server administrators using external tables

  • The sys.computed_columns view shows the correct definition for external tables that use file metadata columns.5

Replication

2 items
  • Manual change tracking cleanup no longer sets an invalid cleanup version to a negative value when the table name is omitted.6
    Applies when the TableName parameter isn't passed to the manual change tracking cleanup stored procedure.
  • Updates to a second article replicate correctly in the specified two-article setup when accelerated database recovery is enabled.7
    Applies to replication with two articles for a single table when accelerated database recovery (ADR) is enabled on the database.

Search

  • Full-text search correctly indexes a hyperlink in a .docx file when it starts a paragraph and the previous paragraph has no trailing whitespace.8
    Trace flag 7686 must be enabled for this fix.

SQL Agent

  • The SQL Server Agent history cleanup job no longer logs a failed login when its service account lacks permission to connect to another instance.9
    Fixes the 'Erase Phantom System Health Records' step in syspolicy_purge_history and the resulting error 18456, state 5.

Patching

For: SQL Server administrators installing SQL Server

  • SQL Server Setup no longer allows Data Quality Services to be installed in Standard or Web edition. This applies to new installations only.10
    DQS is supported only in SQL Server Enterprise and Developer editions. The fix also prevents its automatic selection during Windows Server Failover Cluster setup.

Improvement 1 change

High Availability and Disaster Recovery

For: SQL Server administrators using contained availability groups

  • Contained availability groups can use Resource Governor workload groups defined at the SQL Server instance level.11

Known issues

  1. Open Affects: Everyone

    Incorrect behavior of SESSION_CONTEXT in parallel plans

    Queries using SESSION_CONTEXT might return incorrect results or trigger access violation dump files when run in parallel query plans, particularly if the session is reset for reuse.12

    Workaround status No workaround yet

    Microsoft has not published a manual workaround for this issue yet. Monitor release health until a resolving update is available.

Technical details

Data sheet · Security · Downloads · Components Click to collapse or expand

Data sheet

Released
2025-03-13
Classification
Updates
Type
Cumulative update
Servicing branch
CU
Restart
Required
Replaces
KB5048038, KB5048033, KB5041321, KB5038325
+3 earlier KB5036432, KB5033663, KB5032679
Replaced by
KB5054531
VersionBuildChannel
2022 16.0.4185.3 General availability

Security

No vulnerabilities are listed for this update.

Downloads (Microsoft Update Catalog)

Package 2022
461.2 MB
sqlserver2022-kb5050771-x64.exe Main update · KB5050771 SHA-1: 233edb6e…930753

Sources

Updated
Cited passages from Microsoft's official notes (12)
  1. 1. Fixes an issue in which a copy-only filegroup backup on an availability group secondary replica fails with the following errors: support.microsoft.com
  2. 2. Fixes a race condition that you encounter during flush operations when configuring control.alternatewritethrough = 1, which causes extended waits for some transactions. support.microsoft.com
  3. 3. Fixes an issue in which a self-signed certificate created for SQL Server on Linux might include a negative serial number. support.microsoft.com
  4. 4. Fixes an issue in Database Mail in which the information logged into the sysmail_log system table and sysmail_event_log view in the msdb database might be stored and displayed as "???" support.microsoft.com
  5. 5. Fixes an issue in which the sys.computed_columns view doesn't show the proper definition when using external tables with file metadata columns. support.microsoft.com
  6. 6. Fixes an issue in which the manual change tracking cleanup stored procedure incorrectly sets the invalid cleanup version to negative when the TableName parameter isn't passed. support.microsoft.com
  7. 7. Fixes an issue in which the second article might not have updates correctly replicated if accelerated database recovery (ADR) is enabled on the database using replication with two articles for a single table. support.microsoft.com
  8. 8. Fixes incorrect results that you encounter when you create a full-text index for a .docx file that contains a hyperlink at the start of a paragraph but without a trailing whitespace at the end of the previous paragraph support.microsoft.com
  9. 9. Fixes an error that you encounter when the 'Erase Phantom System Health Records' step in the SQL Server Agent job syspolicy_purge_history tries to connect to other instances and the account running the service doesn't have permission to connect. support.microsoft.com
  10. 10. After applying this fix, SQL Server Setup won't allow DQS to be installed in SQL Server Standard or Web edition. Note: This fix applies to new installations only. support.microsoft.com
  11. 11. Makes the contained availability group (AG) available to use resource governor workload group that's defined at the instance level. support.microsoft.com
  12. 12. 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. support.microsoft.com
Checked automatically: 8 of 8 checks passed, 12 quoted passages · compared with Microsoft's page on Oct 20, 2026
  • Quotes found in the official pages: passed
  • Numbers found in the sources: passed
  • Vulnerabilities from the dossier only: passed
  • Links to allowed domains only: passed
  • Every official change covered: passed
  • Readable plain text: passed
  • Changes confirmed by the file list: passed
  • Sources agree: passed

A second AI read the text against the sources: correctness 3/5, clarity 4/5, completeness 5/5. How we work

Published by The Update Bureau. Written with AI from Microsoft's own documents, checked by rules and a second AI. How we work · Report a mistake