Applies to:

Microsoft .NET Framework 4.8

Summary

Security improvements

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).

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.

  • 4570502 Description of the Security Only Update 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 and Windows Server 2012 R2 (KB4570502)

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

Prerequisites

To apply this update, you must have .NET Framework 4.8 installed.

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:

20200811 Security update deployment information: August 11, 2020

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 The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.Windows 8.1, Windows RT 8.1 and Windows Server 2012 R2 file information

Note: The MANIFEST files (.manifest) and MUM files (.mum) that are installed are not listed.

File information

File hash information

File name

SHA1 hash

SHA256 hash

Windows8.1-KB4569732-x64-NDP48.msu

8A8F8E2B334338398E85708132F948F163953642

043B11E9E1C17E5C09D46ADE64F5974D66C0E8FDE5B7AF07CEB25AC43ACF1A4D

Windows8.1-KB4569732-x86-NDP48.msu

E69089615ECE18DB69AB82995EAE8670522E023D

FE21E010E3C147DDBBBD44FFFDEBD0EF4122349B0DE6C57F80A1331BB0CA9381

Windows8.1-KB4569732-arm-NDP48.msu

CB3AC2648183FC741E8AAD7800417E3FBB53CD57

E4C1FDC061A36DF7EE720D0B2E88486605B166818FD3E128BEC0D9A2CFFE82B4

For all supported x64-based versions

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

Aspnet_perf.dll

4.8.4210.0

41,864

30-Jun-2020

01:38

x64

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

29-Jun-2020

22:16

Not applicable

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

30-Jun-2020

01:39

Not applicable

SPN

AMD64_NETFX4-ASP

Aspnet_wp.exe

4.8.4210.0

45,448

30-Jun-2020

01:38

x64

SPN

AMD64_NETFX4-ASP

System.web.applicationservices.dll

4.8.4210.0

63,752

30-Jun-2020

01:55

x86

None

Not applicable

System.web.extensions.dll

4.8.4210.0

1,842,440

30-Jun-2020

01:55

x86

None

Not applicable

Webengine4.dll

4.8.4210.0

675,200

30-Jun-2020

01:38

x64

None

Not applicable

Webengine.dll

4.8.4210.0

21,384

30-Jun-2020

01:38

x64

None

Not applicable

System.web.dll

4.8.4210.0

5,396,864

30-Jun-2020

01:38

x64

None

Not applicable

System.web.applicationservices.dll

4.8.4210.0

63,752

30-Jun-2020

01:55

x86

None

Not applicable

System.web.extensions.dll

4.8.4210.0

1,842,440

30-Jun-2020

01:55

x86

None

Not applicable

Aspnet_perf.dll

4.8.4210.0

36,224

30-Jun-2020

01:55

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

29-Jun-2020

22:08

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

30-Jun-2020

01:57

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.8.4210.0

39,816

30-Jun-2020

01:55

x86

SPN

X86_NETFX4-ASP

System.web.extensions.dll

4.8.4210.0

1,842,440

30-Jun-2020

01:55

x86

None

Not applicable

Webengine4.dll

4.8.4210.0

564,616

30-Jun-2020

01:55

x86

None

Not applicable

Webengine.dll

4.8.4210.0

19,320

30-Jun-2020

01:55

x86

None

Not applicable

System.web.dll

4.8.4210.0

5,409,152

30-Jun-2020

01:55

x86

None

Not applicable

For all supported x86-based versions

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

System.web.applicationservices.dll

4.8.4210.0

63,752

30-Jun-2020

01:55

x86

None

Not applicable

System.web.extensions.dll

4.8.4210.0

1,842,440

30-Jun-2020

01:55

x86

None

Not applicable

Aspnet_perf.dll

4.8.4210.0

36,224

30-Jun-2020

01:55

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

29-Jun-2020

22:08

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

30-Jun-2020

01:57

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.8.4210.0

39,816

30-Jun-2020

01:55

x86

SPN

X86_NETFX4-ASP

System.web.extensions.dll

4.8.4210.0

1,842,440

30-Jun-2020

01:55

x86

None

Not applicable

Webengine4.dll

4.8.4210.0

564,616

30-Jun-2020

01:55

x86

None

Not applicable

Webengine.dll

4.8.4210.0

19,320

30-Jun-2020

01:55

x86

None

Not applicable

System.web.dll

4.8.4210.0

5,409,152

30-Jun-2020

01:55

x86

None

Not applicable

For all supported ARM-based versions

File name

File version

File size

Date

Time

Platform

System.web.extensions.dll

4.8.4210.0

1,842,440

30-Jun-2020

01:55

x86

System.web.dll

4.8.4210.0

5,416,720

30-Jun-2020

01:36

Not applicable

System.web.applicationservices.dll

4.8.4210.0

63,752

30-Jun-2020

01:55

x86

System.web.extensions.dll

4.8.4210.0

1,842,440

30-Jun-2020

01:55

x86

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