August 14, 2018—KB4343901 (Monthly Rollup)

Improvements and fixes

This security update includes improvements and fixes that were a part of update KB4338816 (released July 18, 2018) and addresses the following issues:

• Provides protections against a new speculative execution side-channel vulnerability known as L1 Terminal Fault (L1TF) that affects Intel® Core® processors and Intel® Xeon® processors (CVE-2018-3620 and CVE-2018-3646). Make sure previous OS protections against Spectre Variant 2 and Meltdown vulnerabilities are enabled using the registry settings outlined in the Windows Server guidance KB article. (These registry settings are disabled by default for Windows Server OS editions.)
• Provides protections against an additional vulnerability involving side-channel speculative execution known as Lazy Floating Point (FP) State Restore (CVE-2018-3665) for 32-Bit (x86) versions of Windows.
  For more information about the resolved security vulnerabilities, see the Security Update Guide.

Known issues in this update

Microsoft is not currently aware of any issues with this update.

How to get this update

This update will be downloaded and installed automatically from Windows Update. To get the standalone package for this update, go to the Microsoft Update Catalog website.File informationFor a list of the files that are provided in this update, download the file information for update 4343901.