You will go from non-Schengen to the Schengen area. KLM flights to Vienna most of the time depart from C/D. Total time needed from gate to gate should be around 25 minutes.
Should normally be no problem, your baggage should be labelled through all the way to VIE.
However if your plane is delayed and you can't make your connection you will be automatically placed on the next flight that's iirc departing at 14h25 instead of 9h55.