Security and Quality Rollup for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 SP2 (KB4566520)

**Applies to:**Microsoft .NET Framework 2.0 Microsoft .NET Framework 3.0 Microsoft .NET Framework 4.5.2 Microsoft .NET Framework 4.6

Notice

On July 23, 2020, update KB4565616 v2 and KB4565623 v2 were released to replace v1 of those updates for .NET Framework 4.5.2 and 4.6 for Windows Server 2008 SP2. 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.

IMPORTANTVerify thatyou have installed the required updates listed in the How to get this update section before installing this update.

IMPORTANT WSUS scan cab files will continue to be available for Windows Server 2008 SP2. If you have a subset of devices running this operating system 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 this OS 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 in August, 2019, updates to .NET Framework 4.6 and above, for Windows Server 2008 SP2 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&gt;. To learn more about the vulnerabilities, go to the following Common Vulnerabilities and Exposures (CVE).

• CVE-2020-1147

Known issues in some parts of this update

Symptom| This update does not install, and it returns either or both of the following error messages:

• -2146762495
• A required certificate is not within its validity period when verifying against the current system clock or the timestamp in the signed file.
  —|—
  Workaround| For details see the article for the .NET Framework individual product version for detailed instructions.

Additional information about this update

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

• 4565611 Description of the Security and Quality Rollup for .NET Framework 2.0, 3.0 for Windows Server 2008 SP2 (KB4565611)
• 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 for Windows 7 SP1 and Windows Server 2008 R2 SP1 and Windows Server 2008 SP2 (KB4565623)

Information about protection and security

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