Yes, You had the oil level a bit over filled. The crankcase blows out of the vent system into the frame. At the top of the frame under the tank, the excess oil in the frame then can vent into a hose to the air box.
There is an airbox drain hose behind the seat/helmet key lock. If there is a bit too much oil in the airbox, that will drip onto the ground.
A little of it is normal. If it is excessive, and it starts draining out of the airbox, you may want to verify that the oil level is not too high.
