MS16-020: Security update for Active Directory Federation Services to address denial of service: February 9, 2016

This security update resolves a vulnerability in Active Directory Federation Services (AD FS). The vulnerability could allow denial of service if an attacker sends certain input data during forms-based authentication to an AD FS server. This scenario causes the server to become unresponsive. 

To learn more about the vulnerability, see Microsoft Security Bulletin MS16-020.
More information
  • 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, seeGet security updates automatically.

Method 2: Microsoft Download Center

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 MS16-020 that corresponds to the version of Windows that you are running.
More information

Security update deployment information

Windows Server 2012 R2 (all editions)

Reference table

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

Security update file nameFor all supported editions of Windows Server 2012 R2:
Installation switchesSee Microsoft Knowledge Base article 934307
Restart requirementIn some cases, this update does not require a system restart. If the required files are being used, this update will require a system restart. If this behavior occurs, you receive a message that advises you to restart your system.
Removal informationTo uninstall an update installed by WUSA, use the /Uninstall setup switch. Or, click Control Panel, click System and Security, click Windows Update, and under See also, click Installed updates, and then select from the list of updates.
File informationSee the File information section.
Registry key verificationNote There is no registry key 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 nameSHA1 hashSHA256 hash

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 R2 file information

  • 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. 

    VersionProductMilestoneService branch
    6.3.960 0.17xxxWindows Server 2012 R2RTMGDR
  • 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 nameFile versionFile sizeDateTimePlatform
Microsoft.identityserver.proxyservice.exe.configNot applicable1,06715-Mar-201400:10Not applicable
malicious attacker exploit

Article ID: 3134222 - Last Review: 02/09/2016 18:03:00 - Revision: 1.0

Windows Server 2012 R2 Datacenter, Windows Server 2012 R2 Standard, Windows Server 2012 R2 Essentials, Windows Server 2012 R2 Foundation

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