Can commercial airliners fly over hurricanes?
In general, no- except in emergencies or 'small' hurricanes.


Commercial aircraft usually fly around bad weather (like hurricanes), not over it.
Some of the hurricanes can reach upto 50,000+ ft height, making it all but impossible for most modern commercial aircraft to fly over them (except maybe you're flying a Concorde). Even for smaller storms, the convective process over the hurricane will cause severe turbulence, affecting overflying flights.
Even for hurricanes where the  aircraft can fly over, there is the problem of safety- What will happen is something happens (for example engine failure) and the aircraft has to descend to lower altitudes? Obviously no one wants to descend into the storm.
There are some aircraft that do fly into hurricanes for scientific experiments. These are crewed by trained (and experienced) specialists and involve a lot of detailed planning. For example, the aircraft are equipped with radar that helps in avoiding the worst parts of the storm. Still, it is risky and the aircraft is exposed to significant loads and vibrations not usually exposed in commercial service.