Internet Explorer zero-day
This time around, the zero day is related to Internet Explorer and activex… (directanimation specifically). Incidents has a good update on the issue. This is a second exploit, there was another at the end of August, MS has an advisory on the issue. I think a safe bet would be alternative browsers until this is patched. It is possible though to enable a kill bit, or vary security settings to disable/always prompt before using activex.