More information, including two papers on the CPU issues, has been released. The papers on the two bugs, called “Meltdown” and “Spectre” are available from: https://meltdownattack.com/. These papers are technical descriptions of the bugs. Meltdown works on Intel processors only, Spectre works on Intel, AMD, and ARM processors.
Microsoft released patches today – the patch is not enabled by default and has to be enabled manually after the patch is applied. In addition, the patch will not be available for systems that are running incompatible anti-virus – some AV packages make calls into kernel memory that will cause a blue-screen-of-death if the patch is applied and enabled. More information from Microsoft is available here:
https://support.microsoft.com/en-us/help/4072699/important-information-regarding-the-windows-security-updates-released
A security researcher has a Google Docs spreadsheet of the status of AV products here:
https://docs.google.com/spreadsheets/d/184wcDt9I9TUNFFbsAVLpzAtckQxYiuirADzf3cL42FQ/edit#gid=0
Windows Server Guidance to protect against the speculative execution side-channel vulnerabilities:
https://support.microsoft.com/en-us/help/4072698/windows-server-guidance-to-protect-against-the-speculative-execution-s
Windows Client Guidance for IT Pros to protect against speculative execution side-channel vulnerabilities:
https://support.microsoft.com/en-us/help/4073119/windows-client-guidance-for-it-pros-to-protect-against-speculative-exe
List of Meltdown and Spectre Vulnerability Advisories, Patches, & Updates:
https://www.bleepingcomputer.com/news/security/list-of-meltdown-and-spectre-vulnerability-advisories-patches-and-updates/
A Simple Explanation of the Differences Between Meltdown and Spectre:
https://danielmiessler.com/blog/simple-explanation-difference-meltdown-spectre/
Reportedly MacOS 10.13.2 has the fixes in it and was released December 6, 2017.