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Summary

This security update resolves a vulnerability in Microsoft Windows. The vulnerability could cause denial of service on a Network Policy Server (NPS) if an attacker sends specially crafted username strings to the NPS. This scenario could prevent RADIUS authentication on the NPS. 

To learn more about the vulnerability, see Microsoft Security Bulletin MS16-021.

More Information

Important

  • All future security and nonsecurity updates for Windows Server 2012 R2 require update 2919355 to be installed. We recommend that you install update 2919355 on your Windows Server 2012 R2-based computer so that you receive future updates.

  • 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.

How to obtain and install the update

Method 1: Windows Update

This update is available through Windows Update. When you turn on automatic updating, this update will be downloaded and installed automatically. For more information about how to turn on automatic updating, see
Get security updates automatically.

You can obtain the stand-alone update package through the Microsoft Download Center. Follow the installation instructions on the download page to install the update.

Click the download link in Microsoft Security Bulletin MS16-021 that corresponds to the version of Windows that you are running.

More Information

Security update deployment information

Windows Server 2008 (all editions)Reference table

The following table contains the security update information for this software.

Security update file names

For all supported 32-bit editions of Windows Server 2008:
Windows6.0-KB3133043-x86.msu

For all supported x64-based editions of Windows Server 2008:
Windows6.0-KB3133043-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

In some cases, this update does not require a restart. If the required files are being used, this update will require a restart. If this behavior occurs, you receive a message that advises you to restart. 

For more information about the reasons why you may be prompted to restart, see Microsoft Knowledge Base Article 887012.

Removal information

WUSA.exe does not support uninstall of updates. To uninstall an update that is installed by WUSA, click Control Panel, and then click Security. Under Windows Update, click View installed updates, and then select from the list of updates.

File information

See the file information section.

Registry key verification

Note A registry key does not exist to validate the presence of this update.

Windows Server 2008 R2 (all editions)Reference table

The following table contains the security update information for this software.

Security update file name

For all supported x64-based editions of Windows Server 2008 R2:
Windows6.1-KB3133043-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

In some cases, this update does not require a restart. If the required files are being used, this update will require a restart. If this behavior occurs, you receive a message that advises you to restart. 

For more information about the reasons why you may be prompted to restart, see Microsoft Knowledge Base Article 887012.

Removal information

To uninstall an update that is installed by WUSA, use the /Uninstall setup switch. Or, click Control Panel, click System and Security, and under Windows Update, click View installed updates, and then select from the list of updates.

File information

See the file information section.

Registry key verification

Note A registry key does not exist to validate the presence of this update.

Windows Server 2012 and Windows Server 2012 R2 (all editions)Reference table

The following table contains the security update information for this software.

Security update file name

For all supported editions of Windows Server 2012:
Windows8-RT-KB3133043-x64.msu

For all supported editions of Windows Server 2012 R2:
Windows8.1-KB3133043-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

In some cases, this update does not require a restart. If the required files are being used, this update will require a restart. If this behavior occurs, you receive a message that advises you to restart. For more information about the reasons why you may be prompted to restart, see Microsoft Knowledge Base Article 887012.

Removal information

To uninstall an update that is installed by WUSA, use the /Uninstall setup switch. Or, click Control Panel, click System and Security, and under Windows Update, click View installed updates, and then select from the list of updates.

File information

See the file information section.

Registry key verification

Note A registry key does not exist to validate the presence of this update.

How to obtain help and support for this security update

Help for installing updates: Support for Microsoft Update

Security solutions for IT professionals: TechNet Security Troubleshooting and Support

Help for protecting your Windows-based computer from viruses and malware: Virus Solution and Security Center

Local support according to your country: International Support

File Information

File hash information

File name

SHA1 hash

SHA256 hash

Windows8-RT-KB3133043-x64.msu

8D265B3FA94C47D4F031BF4139208B20FAFE3871

4117A699450F26035D3C4292159FBB4E85176F4CB833F6D2A65B08EC3C37092D

Windows8.1-KB3133043-x64.msu

4D4F74206EDCC073BC1C3523F5B642D7B55C2615

27B8B9F8385E976C01FB0C8941F5C363DDBD6A1AF7B4AF561A0F24609E87B908

Windows6.1-KB3133043-x64.msu

43094309E6085F94D44A31F94C6ECBF473F6AD12

AEFCDCF7D8A8D9759BBC1FE4AC0493760F5410AF912D4022BC2816653AEF32AB

Windows6.0-KB3133043-x86.msu

EC383824516669B8D277521499FB547510583608

42EB830CF30A0C773E97143B9A79B70C25284DD2B72899429D70FB261E7C9B7E

Windows6.0-KB3133043-x64.msu

5B5483F7A60B9B2E3B8FF0AA5AD440E0D68B3EB3

750DA59CE2774AFB245D6494C499BDB3E4F017EA3F79E90B71A3614A49287ACD

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

Notes

  • The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:

    Version

    Product

    Milestone

    Service branch

    6.2.920 0.17xxx

    Windows Server 2012

    RTM

    GDR

    6.2.920 0.21xxx

    Windows Server 2012

    RTM

    LDR

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. LDR service branches contain hotfixes in addition to widely released fixes.

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

For all supported x64-based versions

File name

File version

File size

Date

Time

Platform

Iassam.dll

6.2.9200.17623

276,480

10-Jan-2016

15:40

x64

Iassam.dll

6.2.9200.21743

276,480

10-Jan-2016

02:24

x64

Iassam.dll

6.2.9200.17623

219,136

10-Jan-2016

12:04

x86

Iassam.dll

6.2.9200.21743

219,136

10-Jan-2016

00:13

x86

Windows Server 2008 R2 file information

Notes

  • The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:

    Version

    Product

    Milestone

    Service branch

    6.1.760 1.18xxx

    Windows 7 or Windows Server 2008 R2

    SP1

    GDR

    6.1.760 1.23 xxx

    Windows 7 or Windows Server 2008 R2

    SP1

    LDR

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. LDR service branches contain hotfixes in addition to widely released fixes.

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

For all supported x64-based versions

File name

File version

File size

Date

Time

Platform

Iassam.dll

6.1.7601.19114

254,464

08-Jan-2016

18:56

x64

Iassam.dll

6.1.7601.23318

254,464

08-Jan-2016

19:07

x64

Iassam.dll

6.1.7601.19114

192,512

08-Jan-2016

18:37

x86

Iassam.dll

6.1.7601.23318

192,512

08-Jan-2016

18:46

x86

Windows Server 2012 R2 file information

Notes

  • The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:

    Version

    Product

    Milestone

    Service branch

    6.3.960 0.17 xxx

    Windows Server 2012 R2

    RTM

    GDR

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. LDR service branches contain hotfixes in addition to widely released fixes.

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

For all supported x64-based versions

File name

File version

File size

Date

Time

Platform

Iassam.dll

6.3.9600.18191

276,480

08-Jan-2016

17:58

x64

Iassam.dll

6.3.9600.18191

223,232

08-Jan-2016

17:22

x86

Windows Server 2008 file information

Notes

  • The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:

    Version

    Product

    Milestone

    Service branch

    6.0.600 2.19xxx

    Windows Server 2008

    SP2

    GDR

    6.0.600 2.23xxx

    Windows Server 2008

    SP2

    LDR

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. LDR service branches contain hotfixes in addition to widely released fixes.

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

For all supported x86-based versions

File name

File version

File size

Date

Time

Platform

Iassam.dll

6.0.6002.19578

182,784

09-Jan-2016

17:06

x86

Iassam.dll

6.0.6002.23888

182,784

09-Jan-2016

16:33

x86

For all supported x64-based versions

File name

File version

File size

Date

Time

Platform

Iassam.dll

6.0.6002.19578

242,688

09-Jan-2016

16:42

x64

Iassam.dll

6.0.6002.23888

242,688

09-Jan-2016

16:40

x64

Iassam.dll

6.0.6002.19578

182,784

09-Jan-2016

17:06

x86

Iassam.dll

6.0.6002.23888

182,784

09-Jan-2016

16:33

x86

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