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 64-Bit (x64) 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, but disabled by default for Windows Server OS editions).
- Security updates to Windows App Platform and Frameworks, Microsoft Graphics Component, Windows Storage and Filesystems, Windows Cryptography, Windows Datacenter Networking, Windows Wireless Networking, Windows Kernel, and the Microsoft JET Database Engine.
For more information about the resolved security vulnerabilities, please refer to the Security Update Guide.
Known issues in this update
|After installing this update, there may be issues using the Preboot Execution Environment (PXE) to start a device from a Windows Deployment Services (WDS) server configured to use Variable Window Extension. This may cause the connection to the WDS server to terminate prematurely while downloading the image. This issue does not affect clients or devices that are not using Variable Window Extension.|| |
This issue is resolved in KB4503290.
|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: