From Express.co.uk:
Windows users are being urged to update their PCs immediately after a serious vulnerability was discovered over the weekend.
The shocking flaw in this popular operating system was found by researchers working for Google's Project Zero cyber-security operation with them calling it is the worst Windows remote code in recent memory.
The bug could allow hackers to take over any PC simply by sending an infected email, instant message or by getting the user to click on a link in their web browser.
Tavis Ormandy, a vulnerability researcher at Google who discovered the bug, said in a tweet "This is crazy bad."
To show how serious the problem is, Microsoft has immediately pushed out a major security update which is available to all users now.
[...]
Anyone using Windows 8, 8.1, 10 and Windows Server operating systems are affected by the bug and should now check for the security update.
Yes, that's right, this "crazy bad" vulnerability has been part of Windows since Windows 8, and is only being found and patched now. In other news, it seems that Windows 8 and Windows 10 really are the same operating system, just with different UIs. Still on Windows 7? No worries, brah, you're still good.
On the plus side, Microsoft did work quite quickly to patch this one, something which Mr. Ormandy praised them for, but that doesn't alter the basic fact that 1) there is no such thing as perfect security, and 2) even if there were such a thing, Windows 10 is not that thing.