Depending on your skill level and how much time you want to spend, you can:
Remove the handle and reattach the ferrule with some glue (I'd recommend epoxy)
Don't remove the handle and reattach the ferrule with some glue (I'd recommend epoxy again). This method would involve sliding the ferrule as far forward as you can, applying epoxy to the exposed wood underneath, sliding the ferrule back down and cleaning up any epoxy that oozes out.
Make, or have made, a custom handle.