Ummm...I suppose but what is your goal?
Malt extract is for makign beer, not hard cider. if you add LME or DME to cider, it won't be cider anymore...but some kind of fusion of cider and beer.
it may taste great...it may taste like donkey taint.
So, why are you thinking of trying this? And if you do, I would boil the extract for 10 minutes to make it sanitary. No need to go the full hour.