Applies to:

Microsoft .NET Framework 3.5

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.

Summary

Security Improvements

This security update addresses an issue where an unauthenticated attacker could cause a denial of service on an affected system. For more information please see CVE-2022-26832.

Quality and reliability improvements

There are no new quality and reliability improvements in this release. This update is cumulative and contains all previously released quality and reliability improvements.

Known issues in this update

Microsoft is not currently aware of any issues in this update.

Additional information about this update

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

  • 5012331 Description of the 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 8.1, RT 8.1, and Windows Server 2012 R2 (KB5012331)

How to obtain and install the update

Before installing this update

Prerequisite:

To apply this update, you must have .NET Framework 3.5 installed.

Install this update

Release Channel

Available

Next Step

Windows Update and Microsoft Update

Yes

None. This update will be downloaded and installed automatically from Windows Update.

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, RT 8.1, and Windows Server 2012 R2

Classification: Security Updates

Restart requirement

You may need to 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:

20220412 Security update deployment information: April 12, 2022

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.

Update replacement information

This update replaces previously released updates KB5009721 and KB5010583.

File Information

File hash information

File name

SHA256 hash

Windows8.1-KB5012139-x64.msu

411A545A7E5B6EFCCE3CA68E9E53D4C53F18049EEAB95D611A60B01540525D40

Windows8.1-KB5012139-x86.msu

951C1EFA279FFF2F7885967270706C3AFBA9308125893A4EF9A40402E8C09CBB

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

Aspnet_wp.exe

2.0.50727.8962

46,520

25-Feb-2022

01:31

x64

SPN

AMD64_NETFX-ASP

System.web.regularexpressions.dll

2.0.50727.8962

98,304

25-Feb-2022

01:31

x86

None

Not applicable

Webengine.dll

2.0.50727.8962

750,000

25-Feb-2022

01:31

x64

None

Not applicable

System.web.dll

2.0.50727.8962

5,300,224

25-Feb-2022

01:31

x64

None

Not applicable

System.web.regularexpressions.dll

2.0.50727.8962

98,304

25-Feb-2022

01:25

x86

None

Not applicable

Aspnet_wp.exe

2.0.50727.8962

33,680

25-Feb-2022

01:25

x86

SPN

X86_NETFX-ASP

Webengine.dll

2.0.50727.8962

440,720

25-Feb-2022

01:25

x86

None

Not applicable

System.web.dll

2.0.50727.8962

5,292,032

25-Feb-2022

01:25

x86

None

Not applicable

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

System.web.regularexpressions.dll

2.0.50727.8962

98,304

25-Feb-2022

01:25

x86

None

Not applicable

Aspnet_wp.exe

2.0.50727.8962

33,680

25-Feb-2022

01:25

x86

SPN

X86_NETFX-ASP

Webengine.dll

2.0.50727.8962

440,720

25-Feb-2022

01:25

x86

None

Not applicable

System.web.dll

2.0.50727.8962

5,292,032

25-Feb-2022

01:25

x86

None

Not applicable

Information about protection and security

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