Applies ToWindows 10 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 8 Enterprise Windows 8 Pro Windows 8 Windows RT 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

This security update resolves a security feature bypass in Microsoft Windows. An attacker could bypass Kerberos authentication on a computer and decrypt drives that have BitLocker enabled. The bypass can be exploited only if the computer has BitLocker enabled without a PIN or USB key, the computer is domain joined, and the attacker has physical access to the computer.To learn more about the vulnerability, see Microsoft Security Bulletin MS15-122.

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

  • 3101246 MS15-122: Description of the security update for Windows Kerberos: November 10, 2015

  • 3105213 Cumulative update for Windows 10: November 10, 2015

  • 3105211 Cumulative update for Windows 10 Version 1511: November 10, 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 and 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 MS15-122 that corresponds to the version of Windows that you are running.

More Information

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-KB3101246-x86.msu

For all supported x64-based editions of Windows Vista:Windows6.0-KB3101246-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 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 Microsoft Knowledge Base Article 3101246

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-KB3101246-x86.msu

For all supported x64-based editions of Windows Server 2008:Windows6.0-KB3101246-x64.msu

For all supported Itanium-based editions of Windows Server 2008:Windows6.0-KB3101246-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 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 Microsoft Knowledge Base Article 3101246

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-KB3101246-x86.msu

For all supported x64-based editions of Windows 7:Windows6.1-KB3101246-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 that is installed by WUSA, use the /Uninstall setup switch. Or, click Control Panel, and then click System and Security. Under Windows Update, click View installed updates, and then select from the list of updates.

File information

See Microsoft Knowledge Base Article 3101246

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-KB3101246-x64.msu

For all supported Itanium-based editions of Windows Server 2008 R2:Windows6.1-KB3101246-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 that is installed by WUSA, use the /Uninstall setup switch. Or, click Control Panel, and then click System and Security. Under Windows Update, click View installed updates, and then select from the list of updates.

File information

See Microsoft Knowledge Base Article 3101246

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 32-bit editions of Windows 8:Windows8-RT-KB3101246-x86.msu

For all supported x64-based editions of Windows 8:Windows8-RT-KB3101246-x64.msu

For all supported 32-bit editions of Windows 8.1:Windows8.1-KB3101246-x86.msu

For all supported x64-based editions of Windows 8.1:Windows8.1-KB3101246-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 that is installed by WUSA, use the /Uninstall setup switch. Or, click Control Panel, click System and Security, and then click Windows Update. Under See also, click Installed updates, and then select from the list of updates.

File information

See Microsoft Knowledge Base Article 3101246

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-KB3101246-x64.msu

For all supported editions of Windows Server 2012 R2:Windows8.1-KB3101246-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 that is installed by WUSA, use the /Uninstall setup switch. Or, click Control Panel, click System and Security, and then click Windows Update. Under See also, click Installed updates, and then select from the list of updates.

File information

See Microsoft Knowledge Base Article 3101246

Registry key verification

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

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-KB3105213-x86.msu

For all supported x64-based editions of Windows 10:Windows10.0-KB3105213-x64.msu

For all supported 32-bit editions of Windows 10 Version 1511:Windows10.0-KB3105211-x86.msu

For all supported x64-based editions of Windows 10 Version 1511:Windows10.0-KB3105211-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 that is installed by WUSA, use the /Uninstall setup switch. Or, click Control Panel, click System and Security, and then click Windows Update. Under See also, click Installed updates, and then select from the list of updates.

File information

See Microsoft Knowledge Base Article 3105213

Registry key verification

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

Package Name

Package Hash SHA 1

Package Hash SHA 2

Windows6.1-KB3101246-x86.msu

8DBBFF07ACFD2527E11278C5244FFFB3A5AB98D2

51EB2BC6E50939F0EF629EDE02F9EA7B94FB3DF0BECF258011B26F5FFB060AA5

Windows6.1-KB3101246-x64.msu

DD54CDBAE8A78634F7811D532BB33B7651D8BCA0

BB033BB00FE625BD14E051E5781DB531FC8DDE4E4AE1A8BE60769274C7C207E2

Windows8-RT-KB3101246-x86.msu

029C4F3EEB37C6C3F23EB4759A25D961B1412072

190DF15FFB4882897009043C87D913D965E045ADF34E0EBAE0DF7F82C9BD51F2

Windows8-RT-KB3101246-x64.msu

471AE473E52E44F080B8F10A4D9A419619EA04B0

C4FD66EB48CEB202EF464978DC5E2EA9E7A2B683C2C9BF987A8CFA9B1C950483

Windows8.1-KB3101246-x86.msu

78B558E3B8D6BDD3B51266AB35A2821FCE96AEA6

E0B9B83E78A0E1561FC9E85E7E1F567269DA8CB59C46064E090F904EC697FF5D

Windows8.1-KB3101246-x64.msu

7C07350E0AAB83DD9DE6EE64404CD87AC3787B69

6E25F6AB83604AEC497D3BCB38705E196A93D7BC10E27ED491D7DD04236B434C

Windows8-RT-KB3101246-arm.msu

E2A8ABB2CFC35641B6FFECBD9C2D6185B72D36CA

B3EF599DDEAF261EBA624895C46438B67AB21E8C55005D678B78B31A070CC295

Windows8.1-KB3101246-arm.msu

BD94F5C9A9C630510ED61902873A550ABD284D69

E412D04C3E639D00264D8410E9B0884CA6F324639E8DA9F99DD6F78C6B3F0637

Windows6.0-KB3101246-x86.msu

20B408C5A33759B02342F0BA608D320938B5DC87

454D38872FEB4B308A9AAF3CC74525C55394CF0453B2B58AC88853AB3FA4E4D5

Windows6.0-KB3101246-x86.msu

20B408C5A33759B02342F0BA608D320938B5DC87

454D38872FEB4B308A9AAF3CC74525C55394CF0453B2B58AC88853AB3FA4E4D5

Windows6.0-KB3101246-ia64.msu

38B1C93A2D2BF3F271719F48EF672AF29EF89B9C

4713B645576D6EC3168307AB7AA036F8BE2008C9185BFBB3CC4A528C48553BA6

Windows6.0-KB3101246-x64.msu

ABF282EAADA0775D26BC4D789A1EE431EC40B917

BFB736C090C7D31F895808920A2D488C19C0F362993606941CD07C63D16F6D38

Windows6.0-KB3101246-x64.msu

ABF282EAADA0775D26BC4D789A1EE431EC40B917

BFB736C090C7D31F895808920A2D488C19C0F362993606941CD07C63D16F6D38

Windows6.1-KB3101246-ia64.msu

45A5B90000D364B2B8CB60305A57F7327FFB62CC

CCB92A571D1B70E5FD684FF9E2426F1A7E7DADD7B5259ACEF07D608F51CC9459

Windows6.1-KB3101246-x64.msu

DD54CDBAE8A78634F7811D532BB33B7651D8BCA0

BB033BB00FE625BD14E051E5781DB531FC8DDE4E4AE1A8BE60769274C7C207E2

Windows6.1-KB3101246-x64.msu

DD54CDBAE8A78634F7811D532BB33B7651D8BCA0

BB033BB00FE625BD14E051E5781DB531FC8DDE4E4AE1A8BE60769274C7C207E2

Windows8-RT-KB3101246-x64.msu

471AE473E52E44F080B8F10A4D9A419619EA04B0

C4FD66EB48CEB202EF464978DC5E2EA9E7A2B683C2C9BF987A8CFA9B1C950483

Windows8-RT-KB3101246-x64.msu

471AE473E52E44F080B8F10A4D9A419619EA04B0

C4FD66EB48CEB202EF464978DC5E2EA9E7A2B683C2C9BF987A8CFA9B1C950483

Windows8.1-KB3101246-x64.msu

7C07350E0AAB83DD9DE6EE64404CD87AC3787B69

6E25F6AB83604AEC497D3BCB38705E196A93D7BC10E27ED491D7DD04236B434C

Windows8.1-KB3101246-x64.msu

7C07350E0AAB83DD9DE6EE64404CD87AC3787B69

6E25F6AB83604AEC497D3BCB38705E196A93D7BC10E27ED491D7DD04236B434C

Windows6.0-KB3101246-x86.msu

20B408C5A33759B02342F0BA608D320938B5DC87

454D38872FEB4B308A9AAF3CC74525C55394CF0453B2B58AC88853AB3FA4E4D5

Windows6.0-KB3101246-x64.msu

ABF282EAADA0775D26BC4D789A1EE431EC40B917

BFB736C090C7D31F895808920A2D488C19C0F362993606941CD07C63D16F6D38

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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