Applies ToWindows 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 8 Enterprise Windows 8 Pro Windows 8 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

Summary

This security update resolves vulnerabilities in Windows that could allow remote code execution in a host context if a specially crafted application is run by an authenticated and privileged user on a guest virtual machine that is hosted by Hyper-V. An attacker must have valid logon credentials for a guest virtual machine to exploit this vulnerability. To learn more about the vulnerability, see Microsoft Security Bulletin MS15-068.

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.

More 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.

  • 3046359 MS15-068: Description of the security update for Windows Hyper-V: July 14, 2015

  • 3046339 MS15-068: Description of the security update for Windows Hyper-V: July 14, 2015

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 MS15-068 that corresponds to the version of Windows that you are running.

More Information

Windows Server 2008 (all editions)Reference tableThe following table contains the security update information for this software.

Security update file names

For all supported x64-based editions of Windows Server 2008:Windows6.0-KB3046359-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

Yes, you must restart your system 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 3046359

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-KB3046359-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

Yes, you must restart your system 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 3046359

Registry key verification

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

Windows 8 and Windows 8.1 (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 8.1:Windows8.1-KB3046339-x64.msu

For all supported x64-based editions of Windows 8.1:Windows8.1-KB3046359-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

Yes, you must restart your system 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 3046359

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-KB3046339-x64.msu

For all supported editions of Windows Server 2012:Windows8-RT-KB3046359-x64.msu

For all supported editions of Windows Server 2012 R2:Windows8.1-KB3046339-x64.msu

For all supported editions of Windows Server 2012 R2:Windows8.1-KB3046359-x64.msu

Installation switches

See Microsoft Knowledge Base Article 934307

Restart requirement

Yes, you must restart your system 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 3046359

Registry key verification

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

File name

SHA1 hash

SHA256 hash

Windows6.0-KB3046339-x64.msu

BE0C3EBAA0E857DD74AD76F10045359221A2780B

868D8D7D5DA0D8F93CFBCF3DB5F5A26C803085CBC4874FF1DA95D4265074CA7B

Windows6.1-KB3046339-x64.msu

97A48BD2C7E72451B238AF1438D25AE288822012

3F1C5F0B83011FA58B9DDCB8EBA0E05A74CA5EA29A2640A0C9D7C9E6CF69249C

Windows8.1-KB3046339-x64.msu

B24B39E3D681358A888945686B0F6DBFCBB94E1E

B2491F3C6689B9CC65602A0DF8C235E173D6A6D88088CAC492D45B348BE05DDB

Windows8.1-KB3046359-x64.msu

55171DFE080DBA3F91414135D247AB151F42CB28

4AF3AE4D0C826BD633FF906CDCE873114FD48C7DFE8E87593489E35193245FF4

Windows8-RT-KB3046339-x64.msu

1DB8F366F714295FE0823F8B610623EDDA815A8B

B48934AD90D61480DD6C14ACAD9E0C0329B23DD288AD72E9226E9A83EC6CCB78

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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