Unfortunately, we can never assume that malt flavoring is gluten free. It is normally prepared from barley, and is therefore gluten toxic. It’s possible to prepare malt flavoring from other grains. If you have any evidence that this is being done, please e-mail me at firstname.lastname@example.org or leave a comment at the end of this or any article. I would be honored to publish the good news. In the meantime, read every ingredients label and reject any products containing malt, malt flavoring, or malt extract.
This issue is a concrete reminder of the difference between the terms “gluten free” and “wheat free”. Many cereals are wheat free, but the presence of malt flavoring rendering them off-limits to us. Much beer is wheat free, but the malt that it contains is derived from barley.