I have a feeling that I have heard of an exception - either based on the material or the oxidizer.
Yes, every combustion reaction is a redox reaction. Combustion is an exothermic reaction of a fuel and an oxidant (that's a big clue). Most commonly, the oxidant is oxygen, which is reduced to water in the process. The other products will depend on the fuel. Organic compounds will have carbon atoms of various oxidation states that will be oxidized to the +4 state as carbon dioxide product.
Combustion is also called oxidation of a hydrocarbon, however, this means that a hydrocarbon become oxidized while oxygen atom will be reduced. Almost every reaction involves the transfer and gaining of electrons. So since redox is reduction and oxidation then combustion is a redox reaction.