Description of the security update for Office Online Server: January 9, 2018

Applies to: Office Online Server - duplicate (do not use)


This security update resolves vulnerabilities in Microsoft Office that could allow remote code execution if a user opens a specially crafted Office file. To learn more about these vulnerabilities, see Microsoft Common Vulnerabilities and Exposures CVE-2018-0792 and Microsoft Common Vulnerabilities and Exposures CVE-2018-0797.

Note To apply this security update, you must have the release version of Office Online Server installed on the computer.

Known issues

Microsoft is aware of an issue that may cause the installation of this update to fail. This issue is resolved in security update 4011022. For more information, go to the following article in the Microsoft Knowledge Base:

How to get and install the update

Method 1: Microsoft Update Catalog

To get the stand-alone package for this update, go to the Microsoft Update Catalog website.

Method 2: Microsoft Download Center

You can get the stand-alone update package through the Microsoft Download Center. Follow the installation instructions on the download page to install the update.

More Information

Security update deployment information

For deployment information about this update, see security update deployment information: January 9, 2018.

Security update replacement information

This security update replaces previously released security update KB 4011020.

File hash information

Package Name Package Hash SHA 1 Package Hash SHA 2
wacserver2016-kb4011021-fullfile-x64-glb.exe B6190A3806A8CF468F9B34844783DD9DB48EF800 B77702207B63758325F0962CDCE14504B6144D5660C45FBD97BEDB2D7526C5CB

File information

For the list of files that cumulative update 4011021 contains, download the file information.

How to get help and support for this security update

Help for installing updates: Windows Update FAQ

Security solutions for IT professionals: Security Support and Troubleshooting

Help for protecting your Windows-based computer from viruses and malware: Microsoft Secure

Local support according to your country: International Support

Propose a feature or provide feedback on SharePoint: SharePoint User Voice portal