Security and Quality Rollup for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows 7 SP1 and Windows Server 2008 R2 SP1 (KB4566517)

Applies to:

Microsoft .NET Framework 3.5.1 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

Notice

On July 23, 2020, update KB4565616 v2, KB4565623 v2, and KB4565636 v2 were released to replace v1 of those updates for .NET Framework 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, and 4.8 for Windows 7 Service Pack 1 (SP1) and Windows Server 2008 R2 SP1. The v1 updates did not install for customers who had certain ESU configurations.  The v2 updates correct the issue for customers who could not install the v1 updates.  


If you have already installed v1 of these updates, no action is necessary.  


To obtain v2 of these updates, see the “How to obtain and install the update” section of the individual update article.  Links to each article are found in the "Additional information about this update section" of this article.

IMPORTANT Verify that you have installed the required updates listed in the How to get this update section before installing this update. 

IMPORTANT Some customers who use Windows Server 2008 R2 SP1 and have activated their ESU multiple activation key (MAK) add-on before installing the January 14, 2020 updates might need to re-activate their key. Re-activation on the affected devices should only be required once.  For information on activation, see this blog post.

IMPORTANT WSUS scan cab files will continue to be available for Windows 7 SP1 and Windows Server 2008 R2 SP1. If you have a subset of devices running these operating systems without ESU, they might show as non-compliant in your patch management and compliance toolsets.

IMPORTANT Customers who have purchased the Extended Security Update (ESU) for on-premises versions of these operating systems must follow the procedures in KB4522133 to continue receiving security updates after extended support ends on January 14, 2020. For more information on ESU and which editions are supported, see KB4497181.

IMPORTANT Starting on January 15, 2020, a full-screen notification will appear that describes the risk of continuing to use Windows 7 Service Pack 1 after it reaches end of support on January 14, 2020. The notification will remain on the screen until you interact with it. This notification will only appear on the following editions of Windows 7 Service Pack 1:

Note The notification will not appear on domain-joined machines or machines in kiosk mode.

IMPORTANT Starting in August, 2019, updates to .NET Framework 4.6 and above, for Windows Server 2008 R2 SP1, and Windows 7SP1, require SHA-2 Code signing support. Please make sure that you have all the latest Windows Updates before applying this update to avoid installation issues. For more detailed information about SHA-2 code signing support updates, please see KB 4474419.

IMPORTANT All updates for .NET Framework 4.7.2, 4.7.1, 4.7, 4.6.2, 4.6.1, and 4.6 require that the d3dcompiler_47.dll update is installed. We recommend that you install the included d3dcompiler_47.dll update before you apply this update. For more information about the d3dcompiler_47.dll, see KB 4019990.

IMPORTANT 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

A remote code execution vulnerability exists in .NET Framework when the software fails to check the source markup of XML file input. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the process responsible for deserialization of the XML content. To exploit this vulnerability, an attacker could upload a specially crafted document to a server utilizing an affected product to process content. The security update addresses the vulnerability by correcting how .NET Framework validates the source markup of XML content.

This security update affects how .NET Framework's System.Data.DataTable and System.Data.DataSet types read XML-serialized data. Most .NET Framework applications will not experience any behavioral change after the update is installed. For more information on how the update affects .NET Framework, including examples of scenarios which may be affected, please see the DataTable and DataSet security guidance document at https://go.microsoft.com/fwlink/?linkid=2132227.

To learn more about the vulnerabilities, go to the following Common Vulnerabilities and Exposures (CVE).

Additional information about this update

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

  • 4565612 Description of the Security and Quality Rollup for .NET Framework 3.5.1 for Windows 7 SP1 and Windows Server 2008 R2 SP1 (KB4565612)

  • 4565616 Description of the Security and Quality Rollup for .NET Framework 4.5.2 for Windows 7 SP1 and Windows Server 2008 R2 SP1 and Windows Server 2008 SP2 (KB4565616)

  • 4565623 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 7 SP1 and Windows Server 2008 R2 SP1 and Windows Server 2008 SP2 (KB4565623)

  • 4565636 Description of the Security and Quality Rollup for .NET Framework 4.8 for Windows 7 SP1 and Windows Server 2008 R2 SP1 (KB4565636)

Information about protection and security

Need more help?

Expand your skills
Explore Training
Get new features first
Join Microsoft Insiders

Was this information helpful?

Thank you for your feedback!

Thank you for your feedback! It sounds like it might be helpful to connect you to one of our Office support agents.

×