Microsoft has issued an out-of-band update that disables patches for the Spectre Variant 2 bug (CVE-2017-5715) The update targets Windows 7 (SP1), Windows 8.1, all versions of Windows 10, and all supported Windows Server distributions. The company said it decided to disable mitigations for the bug after Intel publicly admitted that the microcode updates it developed for this bug caused “higher than expected reboots and other unpredictable system behavior”” that led to “”data loss or corruption”” Microsoft is also providing instructions on how to manually disable these patches via registry keys.”
Source: https://www.bleepingcomputer.com/news/microsoft/microsoft-issues-windows-out-of-band-update-that-disables-spectre-mitigations/