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Applies to:

Microsoft .NET Framework 4.5.2

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 4.5.2 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 8.1 and Windows Server 2012 R2

Classification: Security Updates

Prerequisites

To apply this update, you must have .NET Framework 4.5.2 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-KB4569741-x64.msu

3ECD36E36A986F11045A7C176735568ACA71C5F2

CBC811F1BDCB33FBF6BDA8D6FFFD5E34BC03A89CAAEDEF0F6A7EAC6A2D50FA17

Windows8.1-KB4569741-arm.msu

4D80F2DA121CBA0741F21FC16C5C8C6A84231D31

22BAC648747D78E38753C65009F367A1A064D81170BA4DFCE14BC42C0A157AB4

Windows8.1-KB4569741-x86.msu

342AB7D6185F16F07146BE86C445EE4731F7C0F0

AA616876F14F2D39D455BB68DABC8D1B838B464998D350D4E28F07C97FB8A1BA

For all supported x64-based versions

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

Aspnet_perf.h

Not applicable

7,177

15-Sep-2019

19:35

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_perf2.ini

Not applicable

995,542

15-Sep-2019

19:35

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_perf2_d.ini

Not applicable

31

15-Sep-2019

19:35

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_state_perf.h

Not applicable

318

15-Sep-2019

19:35

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_state_perf.ini

Not applicable

42,996

15-Sep-2019

19:35

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_state_perf_d.ini

Not applicable

36

15-Sep-2019

19:35

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_perf.dll

4.0.30319.36660

38,264

01-Jul-2020

13:22

x64

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

15-Sep-2019

19:35

Not applicable

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

15-Sep-2019

19:35

Not applicable

SPN

AMD64_NETFX4-ASP

Aspnet_wp.exe

4.0.30319.36660

40,840

01-Jul-2020

13:22

x64

SPN

AMD64_NETFX4-ASP

Msvcp120_clr0400.dll

12.0.52660.36660

671,624

01-Jul-2020

13:22

x64

None

Not applicable

Msvcr120_clr0400.dll

12.0.52660.36660

862,600

01-Jul-2020

13:22

x64

None

Not applicable

System.web.applicationservices.dll

4.0.30319.36660

64,272

01-Jul-2020

13:22

x86

None

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:22

x86

None

Not applicable

Webengine4.dll

4.0.30319.36660

614,280

01-Jul-2020

13:22

x64

None

Not applicable

Webengine.dll

4.0.30319.36660

19,848

01-Jul-2020

13:22

x64

None

Not applicable

System.web.dll

4.0.30319.36660

5,451,656

01-Jul-2020

13:22

x64

None

Not applicable

System.web.applicationservices.dll

4.0.30319.36660

64,272

01-Jul-2020

13:18

x86

None

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:18

x86

None

Not applicable

Aspnet_perf.dll

4.0.30319.36660

34,696

01-Jul-2020

13:18

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.0.30319.36660

36,232

01-Jul-2020

13:18

x86

SPN

X86_NETFX4-ASP

Msvcp120_clr0400.dll

12.0.52660.36660

529,800

01-Jul-2020

13:18

x86

None

Not applicable

Msvcr120_clr0400.dll

12.0.52660.36660

868,744

01-Jul-2020

13:18

x86

None

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:18

x86

None

Not applicable

Webengine4.dll

4.0.30319.36660

502,664

01-Jul-2020

13:18

x86

None

Not applicable

Webengine.dll

4.0.30319.36660

17,800

01-Jul-2020

13:18

x86

None

Not applicable

System.web.dll

4.0.30319.36660

5,457,792

01-Jul-2020

13:18

x86

None

Not applicable

For all supported ARM-based versions

File name

File version

File size

Date

Time

Platform

Msvcp120_clr0400.dll

12.0.52660.36660

601,872

01-Jul-2020

13:19

Not applicable

Msvcr120_clr0400.dll

12.0.52660.36660

634,120

01-Jul-2020

13:19

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:19

x86

System.web.dll

4.0.30319.36660

5,465,872

01-Jul-2020

13:19

Not applicable

System.web.applicationservices.dll

4.0.30319.36660

64,272

01-Jul-2020

13:19

x86

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:19

x86

For all supported x86-based versions

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

System.web.applicationservices.dll

4.0.30319.36660

64,272

01-Jul-2020

13:18

x86

None

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:18

x86

None

Not applicable

Aspnet_perf.h

Not applicable

7,177

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX-ASPNET-NONWOW

Aspnet_perf2.ini

Not applicable

995,542

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX-ASPNET-NONWOW

Aspnet_perf2_d.ini

Not applicable

31

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX-ASPNET-NONWOW

Aspnet_state_perf.h

Not applicable

318

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX-ASPNET-NONWOW

Aspnet_state_perf.ini

Not applicable

42,996

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX-ASPNET-NONWOW

Aspnet_state_perf_d.ini

Not applicable

36

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX-ASPNET-NONWOW

Aspnet_perf.dll

4.0.30319.36660

34,696

01-Jul-2020

13:18

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

23-Sep-2018

13:33

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.0.30319.36660

36,232

01-Jul-2020

13:18

x86

SPN

X86_NETFX4-ASP

Msvcp120_clr0400.dll

12.0.52660.36660

529,800

01-Jul-2020

13:18

x86

None

Not applicable

Msvcr120_clr0400.dll

12.0.52660.36660

868,744

01-Jul-2020

13:18

x86

None

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:18

x86

None

Not applicable

Webengine4.dll

4.0.30319.36660

502,664

01-Jul-2020

13:18

x86

None

Not applicable

Webengine.dll

4.0.30319.36660

17,800

01-Jul-2020

13:18

x86

None

Not applicable

System.web.dll

4.0.30319.36660

5,457,792

01-Jul-2020

13:18

x86

None

Not applicable

Information about protection and security

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