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).

Additional information about this update

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

  • 4570501 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 Server 2012 (KB4570501)

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 Server 2012

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 Server 2012 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-RT-KB4569731-x64-NDP48.msu

12357630822CEDE469281F3DE4E061E21DA58730

570AE47B353D544B27E05D2765818B33F5736433F3C150FB0CCBE33E0E2D3178

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

Information about protection and security

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