According to Business Insider;
The processor security flaw that has the tech world abuzz is already being fixed for Windows computers — but the fix doesn’t completely solve the problem, and right now it’s only available for those running the latest version of the operating system.
The security flaw affects Intel, AMD, and ARM processors. It’s been widely reported that fixing it could require most PCs to take a sizable performance hit.
Microsoft started to push out a patch for the vulnerability for Windows 10 computers on Wednesday afternoon. It plans to release fixes for Windows 7 and Windows 8 on Tuesday, according to The Verge.