Applies to:

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

Summary

This security update addresses a denial of service vulnerability in .NET Framework. For more information please see CVE-2021-24111.

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.

  • 4602959 Description of the Security Only Update for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Server 2012 (KB4602959)

How to obtain and install the update

Before installing this update

Prerequisite:

To apply this update, you must have .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 installed.

Install this update

Release Channel

Available

Next Step

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 Products and Classifications as follows:

Product:Windows Server 2012

Classification: Security Updates

Restart requirement

You must restart the computer after you apply this update if any affected files are being used. We recommend that you exit all .NET Framework-based applications before you apply this update.

Update deployment information

For deployment details for this security update, go to the following article in the Microsoft Knowledge Base:

20210209 Security update deployment information: February 9, 2021

Update removal information

Note We do not recommend that you remove any security update. To remove this update, use the Programs and Features item in Control Panel.

Update restart information

This update does not require a system restart after you apply it unless files that are being updated are locked or are being used.

File Information

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

Aspnet_perf.dll

4.7.3770.0

39,304

05-Jan-2021

01:28

x64

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

05-Jan-2021

00:07

Not applicable

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

05-Jan-2021

01:28

Not applicable

SPN

AMD64_NETFX4-ASP

Aspnet_wp.exe

4.7.3770.0

43,920

05-Jan-2021

01:28

x64

SPN

AMD64_NETFX4-ASP

Msvcp120_clr0400.dll

12.0.52519.0

690,008

04-Sep-2020

19:40

x64

None

Not applicable

Msvcr120_clr0400.dll

12.0.52519.0

993,632

04-Sep-2020

19:40

x64

None

Not applicable

System.web.applicationservices.dll

4.7.3770.0

63,768

05-Jan-2021

01:29

x86

None

Not applicable

System.web.extensions.dll

4.7.3770.0

1,842,968

05-Jan-2021

01:29

x86

None

Not applicable

Webengine4.dll

4.7.3770.0

660,360

05-Jan-2021

01:28

x64

None

Not applicable

Webengine.dll

4.7.3770.0

19,336

05-Jan-2021

01:28

x64

None

Not applicable

System.web.dll

4.7.3770.0

5,392,776

05-Jan-2021

01:28

x64

None

Not applicable

System.web.applicationservices.dll

4.7.3770.0

63,768

05-Jan-2021

01:29

x86

None

Not applicable

System.web.extensions.dll

4.7.3770.0

1,842,968

05-Jan-2021

01:29

x86

None

Not applicable

Aspnet_perf.dll

4.7.3770.0

35,720

05-Jan-2021

01:29

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

05-Jan-2021

00:01

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

05-Jan-2021

01:30

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.7.3770.0

39,304

05-Jan-2021

01:29

x86

SPN

X86_NETFX4-ASP

Msvcp120_clr0400.dll

12.0.52519.0

485,576

24-Nov-2020

01:49

x86

None

Not applicable

Msvcr120_clr0400.dll

12.0.52519.0

987,840

24-Nov-2020

01:49

x86

None

Not applicable

System.web.extensions.dll

4.7.3770.0

1,842,968

05-Jan-2021

01:29

x86

None

Not applicable

Webengine4.dll

4.7.3770.0

543,112

05-Jan-2021

01:29

x86

None

Not applicable

Webengine.dll

4.7.3770.0

17,800

05-Jan-2021

01:29

x86

None

Not applicable

System.web.dll

4.7.3770.0

5,410,184

05-Jan-2021

01:29

x86

None

Not applicable

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

System.web.applicationservices.dll

4.7.3770.0

63,768

05-Jan-2021

01:29

x86

None

Not applicable

System.web.extensions.dll

4.7.3770.0

1,842,968

05-Jan-2021

01:29

x86

None

Not applicable

Aspnet_perf.dll

4.7.3770.0

35,720

05-Jan-2021

01:29

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

05-Jan-2021

00:01

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

05-Jan-2021

01:30

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.7.3770.0

39,304

05-Jan-2021

01:29

x86

SPN

X86_NETFX4-ASP

Msvcp120_clr0400.dll

12.0.52519.0

485,576

24-Nov-2020

01:49

x86

None

Not applicable

Msvcr120_clr0400.dll

12.0.52519.0

987,840

24-Nov-2020

01:49

x86

None

Not applicable

System.web.extensions.dll

4.7.3770.0

1,842,968

05-Jan-2021

01:29

x86

None

Not applicable

Webengine4.dll

4.7.3770.0

543,112

05-Jan-2021

01:29

x86

None

Not applicable

Webengine.dll

4.7.3770.0

17,800

05-Jan-2021

01:29

x86

None

Not applicable

System.web.dll

4.7.3770.0

5,410,184

05-Jan-2021

01:29

x86

None

Not applicable

Information about protection and security

Need more help?

Want more options?

Explore subscription benefits, browse training courses, learn how to secure your device, and more.

Communities help you ask and answer questions, give feedback, and hear from experts with rich knowledge.