I don’t know if any of my readers have been following I.T. news in general but there’s a nasty one out there. Has to do with a feature of modern (E.g. the last 25 years) processors – a predictive algorithm is the culprit. It’s what they call a side channel attack.
But if you’re running Windows 7 or Windows 10 you more than likely got an update pushed to your machine yesterday. I know both machines here did updates outside normal schedule so apparently Microsoft pushed the fix.