There are plenty of folk-tales and legends about the old people in Europe. Some of these could be about the neanderthals, although 25,000 years would put it way back in oral tradition.
It's possible.
I read where one anthropologist says that Gigantopithicus (large extinct ape) is the source of our legends/myth of 'boogey men.' The youngest Gigantopithicus skeleton ever found is 600,000 years old.