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).

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 4.5.2 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 Server 2012

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 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-KB4569742-x64.msu

2E2B19886594250BC9F346BD98423EDD8C3E6976

E70A7121CDDF00584E6A046057DD227E655F5BB1F8434D637B0837E0E7E11809

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

04-May-2018

19:43

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_perf2.ini

Not applicable

995,534

04-May-2018

19:43

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_perf2_d.ini

Not applicable

31

04-May-2018

19:43

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_state_perf.h

Not applicable

318

04-May-2018

19:43

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_state_perf.ini

Not applicable

42,996

04-May-2018

19:43

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_state_perf_d.ini

Not applicable

36

04-May-2018

19:43

Not applicable

SPN

AMD64_NETFX-ASPNET-NONWOW

Aspnet_perf.dll

4.0.30319.36660

38,264

01-Jul-2020

13:06

x64

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

04-May-2018

19:43

Not applicable

SPN

AMD64_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

04-May-2018

19:43

Not applicable

SPN

AMD64_NETFX4-ASP

Aspnet_wp.exe

4.0.30319.36660

40,840

01-Jul-2020

13:06

x64

SPN

AMD64_NETFX4-ASP

Msvcp120_clr0400.dll

12.0.52660.36660

671,624

01-Jul-2020

13:06

x64

None

Not applicable

Msvcr120_clr0400.dll

12.0.52660.36660

862,600

01-Jul-2020

13:06

x64

None

Not applicable

System.web.applicationservices.dll

4.0.30319.36660

64,272

01-Jul-2020

13:06

x86

None

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:06

x86

None

Not applicable

Webengine4.dll

4.0.30319.36660

614,280

01-Jul-2020

13:06

x64

None

Not applicable

Webengine.dll

4.0.30319.36660

19,848

01-Jul-2020

13:06

x64

None

Not applicable

System.web.dll

4.0.30319.36660

5,451,656

01-Jul-2020

13:06

x64

None

Not applicable

System.web.applicationservices.dll

4.0.30319.36660

64,272

01-Jul-2020

13:06

x86

None

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:06

x86

None

Not applicable

Aspnet_perf.dll

4.0.30319.36660

34,696

01-Jul-2020

13:06

x86

SPN

X86_NETFX4-ASP

Aspnet_state_perf.h

Not applicable

318

15-Nov-2017

00:50

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_state_perf.ini

Not applicable

42,996

15-Nov-2017

00:50

Not applicable

SPN

X86_NETFX4-ASP

Aspnet_wp.exe

4.0.30319.36660

36,232

01-Jul-2020

13:06

x86

SPN

X86_NETFX4-ASP

Msvcp120_clr0400.dll

12.0.52660.36660

529,800

01-Jul-2020

13:06

x86

None

Not applicable

Msvcr120_clr0400.dll

12.0.52660.36660

868,744

01-Jul-2020

13:06

x86

None

Not applicable

System.web.extensions.dll

4.0.30319.36660

1,852,688

01-Jul-2020

13:06

x86

None

Not applicable

Webengine4.dll

4.0.30319.36660

502,664

01-Jul-2020

13:06

x86

None

Not applicable

Webengine.dll

4.0.30319.36660

17,800

01-Jul-2020

13:06

x86

None

Not applicable

System.web.dll

4.0.30319.36660

5,457,792

01-Jul-2020

13:06

x86

None

Not applicable

Information about protection and security

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