Yes, if you're careful, use short screws. Don't go all the way through the wood/mdf/plastic.
There's a crossover in there somewhere, probably near the speaker terminals, maybe attached to the bottom, you don't want to run a drill or a screw through that.
Lay the speaker on its back, put something pointy (bamboo cooking skewer or similar) gently through the port and see if you can judge the thickness of the back panel.
Maybe you can see into the port to see if something is in the way, or where the crossover is located.
Maybe there are some mounting marks on the back of it already.
Just use good judgment you should be fine.