I have an above ground pool and the skimmer is leaking could it be cracked?

More likely a bad gasket. Before replacing the gasket I would tighten each of the stainles stells bolts that hold the skimmer to the pool, should be about 18 of them. Tighten equally and then check for leakage. There is very little water pressure in this area so tightening might do it for you.

If you do not stop the leakage you will have the same problem as us.. the skimmer leaking will cause the wall to rust and ours has burst/split