Preheat oven to 350 degrees. Line a 12 muffin tin with liners. In a large bowl mix the cake mix, canned pumpkin, eggs, vegetable oil, cinnamon, and nutmeg until incorporated. Fill each liner 2/3 of the way with the batter. Bake for 20-22 minutes or until toothpick comes out clean. Let cool completely before frosting.
To make the frosting: Beat together the cream cheese and butter until creamy. Add the powdered sugar, pumpkin, and cinnamon until smooth and creamy. Frost cooled cupcakes.