Yup. Two screws from the factory. They don't hit anything when folded down because the upper bunk rests against the
fiberglass base several inches out from the front wall. There's enough space to store the banana cushion behind the backrest, sitting vertically in its long edge.
It seems quite secure. We use the upper bunk regularly without issues. If you did want something more secure, I saw where one poster recessed a T-nut in the plywood base and ran a wing bolt through the loop into the T-nut. But then you'd have to keep track of the bolts.