Security and Quality Rollup for .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB5009721)

Applies to: Microsoft .NET Framework 3.5 Microsoft .NET Framework 4.5.2 Microsoft .NET Framework 4.6 Microsoft .NET Framework 4.6.1 Microsoft .NET Framework 4.6.2 Microsoft .NET Framework 4.7 Microsoft .NET Framework 4.7.1 Microsoft .NET Framework 4.7.2 Microsoft .NET Framework 4.8

IMPORTANT

• As a reminder to advanced IT administrators, updates to .NET Framework 3.5 for Windows 8.1 and Windows Server 2012 R2 should only be applied on systems where .NET Framework 3.5 is present and enabled. Customers who attempt to pre-install updates to .NET Framework 3.5 to offline images that do not contain the .NET Framework 3.5 product enabled will expose these systems to failures to enable .NET Framework 3.5 after the systems are online. For more extensive information about deploying .NET Framework 3.5, see Microsoft .NET Framework 3.5 Deployment Considerations.
• All updates for Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2 require that update KB 2919355 is installed. We recommend that you install update KB 2919355 on your Windows 8.1-based, Windows RT 8.1-based, or Windows Server 2012 R2-based computer so that you receive updates in the future.
• If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you need before you install this update. For more information, see Add language packs to Windows

Summary

Security Improvements This security update addresses an issue where an unauthenticated attacker could cause a denial of service on an affected system. For more information please see CVE-2022-21911.Quality ImprovementsFor a list of improvements that were released with this update, please see the article links in the Additional Information section of this article.

Known issues in this update

Microsoft is not currently aware of any issues in this update.

Additional information about this update

The following articles contain additional information about this update as it relates to individual product versions.

• 5008868 Description of the Security and Quality Rollup for .NET Framework 3.5 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB5008868)
• 5008870 Description of the Security and Quality Rollup for .NET Framework 4.5.2 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB5008870)
• 5008875 Description of the Security and Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB5008875)
• 5008883 Description of the Security and Quality Rollup for .NET Framework 4.8 for Windows 8.1, RT 8.1, and Windows Server 2012 R2 (KB5008883)
  Release Channel|Available|Next Step
  —|—|—
  Windows Update and Microsoft Update| Yes| None. This update will be downloaded and installed automatically from Windows Update.
  Microsoft Update Catalog| Yes| To get the standalone package for this update, go to the Microsoft Update Catalog website.
  Windows Server Update Services (WSUS)| Yes| This update will automatically sync with WSUS if you configure as follows: Product: Windows 8.1, RT 8.1, and Windows Server 2012 R2Classification: Security Updates

Information about protection and security

• Protect yourself online: Windows Security support
• Learn how we guard against cyber threats: Microsoft Security