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 Standard Windows Server 2012 Essentials Windows Server 2012 Foundation

Summary

Microsoft has released a Microsoft security advisory about this issue for IT professionals. The security advisory contains additional security-related information. To learn more about the vulnerability, seehttps://technet.microsoft.com/security/advisory/3155527.

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.

  • 3151058 Description of the security update for Schannel: April 12, 2016

  • 3156387Cumulative update for Windows 10: April 12, 2016

  • 3156421Cumulative 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, seeGet security updates automatically. Note For Windows RT 8.1, this update is available through Windows Update only.

The following files are available for download from the Microsoft Download Center.

For all supported x64-based versions of Windows Server 2012 DownloadDownload the package now.

For all supported x86-based versions of Windows 8.1 DownloadDownload the package now.

For all supported x64-based versions of Windows 8.1 DownloadDownload the package now.

For all supported x64-based versions of Windows Server 2012 R2 DownloadDownload the package now.Release Date: May 10, 2016For more information about how to download Microsoft support files, click the following article number to go to the article in the Microsoft Knowledge Base:

119591 How to obtain Microsoft support files from online services

Virus-scan claim

Microsoft scanned this file for viruses by using the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to it.

More Information

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-KB3151058-x86.msu

For all supported x64-based editions of Windows 8.1:Windows8.1-KB3151058-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 3151058

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-KB3151058-x64.msu

For all supported editions of Windows Server 2012 R2:Windows8.1-KB3151058-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 3151058

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

These updates are 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 3151058

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-KB3156387-x86.msu

For all supported x64-based editions of Windows 10:Windows10.0-KB3156387-x64.msu

For all supported 32-bit editions of Windows 10 Version 1511:Windows10.0-KB3156421-x86.msu

For all supported x64-based editions of Windows 10 Version 1511:Windows10.0-KB3156421-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 3156387See Microsoft Knowledge Base Article 3156421

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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