Applies ToWindows 10 Windows 10, version 1511, all editions Windows Server 2012 R2 Datacenter Windows Server 2012 R2 Standard Windows Server 2012 R2 Essentials Windows Server 2012 R2 Foundation Windows 8.1 Enterprise Windows 8.1 Pro Windows 8.1 Windows RT 8.1 Windows Server 2012 Datacenter Windows Server 2012 Datacenter Windows Server 2012 Standard Windows Server 2012 Standard Windows Server 2012 Essentials Windows Server 2012 Foundation Windows Server 2012 Foundation Windows Server 2008 R2 Service Pack 1 Windows Server 2008 R2 Datacenter Windows Server 2008 R2 Enterprise Windows Server 2008 R2 Standard Windows Server 2008 R2 Web Edition Windows Server 2008 R2 Foundation Windows 7 Service Pack 1 Windows 7 Ultimate Windows 7 Enterprise Windows 7 Professional Windows 7 Home Premium Windows 7 Home Basic Windows 7 Starter Windows Server 2008 Service Pack 2 Windows Server 2008 Datacenter Windows Server 2008 Enterprise Windows Server 2008 Standard Windows Server 2008 Web Edition Windows Server 2008 Foundation Windows Server 2008 for Itanium-Based Systems Windows Vista Service Pack 2 Windows Vista Ultimate Windows Vista Enterprise Windows Vista Business Windows Vista Home Premium Windows Vista Home Basic Windows Vista Starter

Summary

An elevation of privilege vulnerability exists in the Security Account Manager (SAM) and Local Security Authority (Domain Policy) (LSAD) remote protocols when they accept authentication levels that do not protect these protocols adequately. The vulnerability is caused by the way the SAM and LSAD remote protocols establish the Remote Procedure Call (RPC) channel. An attacker who successfully exploited this vulnerability could gain access to the SAM database. To learn more about the vulnerability, see Microsoft Security Bulletin MS16-047.

More Information

Important

  • All future security and nonsecurity updates for Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2 require update 2919355 to be installed. We recommend that you install update 2919355 on your Windows RT 8.1-based, Windows 8.1-based, or 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.

Additional information about this security update

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

  • 3149090 MS16-047: Description of the security update for SAM and LSAD remote protocols: April 12, 2016

  • 3147461 Cumulative Update for Windows 10: April 12, 2016

  • 3147458 Cumulative update for Windows 10 Version 1511 and Windows Server 2016 Technical Preview 4: April 12, 2016

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.Note For Windows RT 8.1, this update is available through Windows Update only.

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 MS16-047 that corresponds to the version of Windows that you are running.

Windows Vista (all editions)Reference TableThe following table contains the security update information for this software.

Security update file names

For all supported 32-bit editions of Windows Vista:Windows6.0-KB3149090-x86.msu

For all supported x64-based editions of Windows Vista:Windows6.0-KB3149090-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

A system restart is required after you apply this security update.

Removal information

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

File information

See Microsoft Knowledge Base Article 3149090

Registry key verification

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

Windows Server 2008 (all editions)Reference TableThe 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-KB3149090-x86.msu

For all supported x64-based editions of Windows Server 2008:Windows6.0-KB3149090-x64.msu

For all supported Itanium-based editions of Windows Server 2008:Windows6.0-KB3149090-ia64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

A system restart is required after you apply this security update.

Removal information

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

File information

See Microsoft Knowledge Base Article 3149090

Registry key verification

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

Windows 7 (all editions)Reference TableThe following table contains the security update information for this software.

Security update file name

For all supported 32-bit editions of Windows 7:Windows6.1-KB3149090-x86.msu

For all supported x64-based editions of Windows 7:Windows6.1-KB3149090-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

A system restart is required after you apply this security update.

Removal information

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

File information

See Microsoft Knowledge Base Article 3149090

Registry key verification

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

Windows Server 2008 R2 (all editions)Reference TableThe 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-KB3149090-x64.msu

For all supported Itanium-based editions of Windows Server 2008 R2:Windows6.1-KB3149090-ia64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

A system restart is required after you apply this security update.

Removal information

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

File information

See Microsoft Knowledge Base Article 3149090

Registry key verification

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

Windows 8.1 (all editions)Reference TableThe following table contains the security update information for this software.

Security update file name

For all supported 32-bit editions of Windows 8.1:Windows8.1-KB3149090-x86.msu

For all supported x64-based editions of Windows 8.1:Windows8.1-KB3149090-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

A system restart is required after you apply this security update.

Removal information

To uninstall an update installed by WUSA, use the /Uninstall setup switch or click Control Panel, click System and Security, click Windows Update, and then under See also, click Installed updates and select from the list of updates.

File information

See Microsoft Knowledge Base Article 3149090

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

Security update file name

For all supported editions of Windows Server 2012:Windows8-RT-KB3149090-x64.msu

For all supported editions of Windows Server 2012 R2:Windows8.1-KB3149090-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

A system restart is required after you apply this security update.

Removal information

To uninstall an update installed by WUSA, use the /Uninstall setup switch or click Control Panel, click System and Security, click Windows Update, and then under See also, click Installed updates and select from the list of updates.

File information

See Microsoft Knowledge Base Article 3149090

Registry key verification

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

Windows RT 8.1 (all editions)Reference TableThe following table contains the security update information for this software.

Deployment

The update is available via Windows Update only.

Restart Requirement

A system restart is required after you apply this security update.

Removal Information

Click Control Panel, click System and Security, click Windows Update, and then under See also, click Installed updates and select from the list of updates.

File Information

See Microsoft Knowledge Base Article 3149090

Windows 10 (all editions)Reference TableThe following table contains the security update information for this software.

Security update file name

For all supported 32-bit editions of Windows 10:Windows10.0-KB3147461-x86.msu

For all supported x64-based editions of Windows 10:Windows10.0-KB3147461-x64.msu

For all supported 32-bit editions of Windows 10 Version 1511:Windows10.0-KB3147458-x86.msu

For all supported x64-based editions of Windows 10 Version 1511:Windows10.0-KB3147458-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

A system restart is required after you apply this security update.

Removal information

To uninstall an update installed by WUSA, use the /Uninstall setup switch or click Control Panel, click System and Security, click Windows Update, and then under See also, click Installed updates and select from the list of updates.

File information

See Microsoft Knowledge Base Article 3147461See Microsoft Knowledge Base Article 3147458

Registry key verification

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

Help for installing updates: Support for Microsoft UpdateSecurity solutions for IT professionals: TechNet Security Troubleshooting and SupportHelp for protecting your Windows-based computer from viruses and malware: Virus Solution and Security CenterLocal support according to your country: International Support

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