Improvements and fixes
This security update includes quality improvements. Key changes include:
- Provides protections against a new subclass of speculative execution side-channel vulnerabilities, known as Microarchitectural Data Sampling, for 32-Bit (x86) versions of Windows (CVE-2019-11091, CVE-2018-12126, CVE-2018-12127, CVE-2018-12130). Use the registry settings as described in the Windows Client and Windows Server articles. (These registry settings are enabled by default for Windows Client OS editions and Windows Server OS editions.)
- Security updates to Windows App Platform and Frameworks, Windows Kernel, Windows Input and Composition, Windows Media, Windows Fundamentals, Windows Authentication, Windows Datacenter Networking, Windows Storage and Filesystems, the Microsoft JET Database Engine, and Windows Server.
For more information about the resolved security vulnerabilities, please refer to the Security Update Guide.
Known issues in this update
|Certain operations, such as rename, that you perform on files or folders that are on a Cluster Shared Volume (CSV) may fail with the error, “STATUS_BAD_IMPERSONATION_LEVEL (0xC00000A5)”. This occurs when you perform the operation on a CSV owner node from a process that doesn’t have administrator privilege.|| |
Do one of the following:
How to get this update
Before installing this update
Microsoft strongly recommends you install the latest servicing stack update (SSU) for your operating system before installing the latest Rollup. SSUs improve the reliability of the update process to mitigate potential issues while installing the Rollup and applying Microsoft security fixes.
Install this update
|Release Channel||Available||Next Step|
|Windows Update and Microsoft Update||No||See the other options below.|
|Microsoft Update Catalog||Yes||To get the standalone package for this update, go to the Microsoft Update Catalog website.|
|Windows Server Update Services (WSUS)||Yes|| |
This update will automatically synchronize with WSUS if you configure Products and Classifications as follows:
Product: Windows 8.1, Windows Server 2012 R2Classification: Security Updates
For a list of the files that are provided in this update, download the file information for update 4516064.