Security Only Update for .NET Framework 4.8 for Windows 8.1 and Windows Server 2012 R2 (KB4601092)

Applies to:

Microsoft .NET Framework 4.8

Summary

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

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.

Additional information about this update

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

  • 4602960 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 8.1 and Windows Server 2012 R2 (KB4602960)

How to obtain and install the update

Before installing this update

Prerequisite:

To apply this update, you must have .NET Framework 4.8 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 8.1 and Windows Server 2012 R2

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

4.8.4330.0

41,864

05-Jan-2021

01:27

x64

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

04-Jan-2021

23:56

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

4.8.4330.0

45,456

05-Jan-2021

01:27

x64

SPN

AMD64_NETFX4-ASP

System.web.applicationservices.dll

4.8.4330.0

63,768

05-Jan-2021

01:30

x86

None

Not applicable

System.web.extensions.dll

4.8.4330.0

1,842,448

05-Jan-2021

01:30

x86

None

Not applicable

Webengine4.dll

4.8.4330.0

675,208

05-Jan-2021

01:27

x64

None

Not applicable

Webengine.dll

4.8.4330.0

21,376

05-Jan-2021

01:27

x64

None

Not applicable

System.web.dll

4.8.4330.0

5,397,896

05-Jan-2021

01:27

x64

None

Not applicable

System.web.applicationservices.dll

4.8.4330.0

63,768

05-Jan-2021

01:30

x86

None

Not applicable

System.web.extensions.dll

4.8.4330.0

1,842,448

05-Jan-2021

01:30

x86

None

Not applicable

Aspnet_perf.dll

4.8.4330.0

36,232

05-Jan-2021

01:30

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

04-Jan-2021

23:56

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

05-Jan-2021

01:31

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.8.4330.0

39,824

05-Jan-2021

01:30

x86

SPN

X86_NETFX4-ASP

System.web.extensions.dll

4.8.4330.0

1,842,448

05-Jan-2021

01:30

x86

None

Not applicable

Webengine4.dll

4.8.4330.0

564,616

05-Jan-2021

01:30

x86

None

Not applicable

Webengine.dll

4.8.4330.0

19,328

05-Jan-2021

01:30

x86

None

Not applicable

System.web.dll

4.8.4330.0

5,410,184

05-Jan-2021

01:30

x86

None

Not applicable

File name

File version

File size

Date

Time

Platform

System.web.extensions.dll

4.8.4330.0

1,842,448

05-Jan-2021

01:30

x86

System.web.dll

4.8.4330.0

5,418,264

05-Jan-2021

01:27

Not applicable

System.web.applicationservices.dll

4.8.4330.0

63,768

05-Jan-2021

01:30

x86

System.web.extensions.dll

4.8.4330.0

1,842,448

05-Jan-2021

01:30

x86

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

System.web.applicationservices.dll

4.8.4330.0

63,768

05-Jan-2021

01:30

x86

None

Not applicable

System.web.extensions.dll

4.8.4330.0

1,842,448

05-Jan-2021

01:30

x86

None

Not applicable

Aspnet_perf.dll

4.8.4330.0

36,232

05-Jan-2021

01:30

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

04-Jan-2021

23:56

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

05-Jan-2021

01:31

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.8.4330.0

39,824

05-Jan-2021

01:30

x86

SPN

X86_NETFX4-ASP

System.web.extensions.dll

4.8.4330.0

1,842,448

05-Jan-2021

01:30

x86

None

Not applicable

Webengine4.dll

4.8.4330.0

564,616

05-Jan-2021

01:30

x86

None

Not applicable

Webengine.dll

4.8.4330.0

19,328

05-Jan-2021

01:30

x86

None

Not applicable

System.web.dll

4.8.4330.0

5,410,184

05-Jan-2021

01:30

x86

None

Not applicable

Information about protection and security

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