Preheat oven to 350 degrees F (175 degrees C). Grease a 9x13-inch pan.
Mix cake mix, pumpkin puree, vegetable oil, eggs, and pumpkin pie spice together in a bowl; pour into the prepared pan.
Bake in the preheated oven until a toothpick inserted in the center of the cake comes out clean, about 20 minutes; remove from oven and cool cake completely.
Beat cream cheese, butter, and vanilla extract together in a bowl until light and creamy. Gradually beat confectioners' sugar into mixture until smooth; spread onto cooled cake.
