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 Server 2012 (KB4570507)

**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

Summary

An elevation of privilege vulnerability exists when ASP.NET or .NET Framework web applications running on IIS improperly allow access to cached files. An attacker who successfully exploited this vulnerability could gain access to restricted files. To exploit this vulnerability, an attacker would need to send a specially crafted request to an affected server. The update addresses the vulnerability by changing how ASP.NET and .NET Framework handle requests. To learn more about the vulnerabilities, go to the following Common Vulnerabilities and Exposures (CVE).

• CVE-2020-1476
  A remote code execution vulnerability exists when Microsoft .NET Framework processes input. An attacker who successfully exploited this vulnerability could take control of an affected system. To exploit the vulnerability, an attacker would need to be able to upload a specially crafted file to a web application. The security update addresses the vulnerability by correcting how .NET Framework processes input. For more information go to: <https://go.microsoft.com/fwlink/?linkid=2138023&gt; To learn more about the vulnerabilities, go to the following Common Vulnerabilities and Exposures (CVE).

• CVE-2020-1046
  For a list of improvements that were released with this update, please see the article links in the Additional Information section of this article.Important

• All updates for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, and 4.7.2 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.

• 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.

Additional information about this update

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

• 4569765 Description of the Security and Quality Rollup for .NET Framework 3.5 for Windows Server 2012 (KB4569765)
• 4569779 Description of the Security and Quality Rollup for .NET Framework 4.5.2 for Windows Server 2012 (KB4569779)
• 4569773 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 Server 2012 (KB4569773)
• 4569752 Description of the Security and Quality Rollup for .NET Framework 4.8 for Windows Server 2012 (KB4569752)

Information about protection and security

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