Combine 3 cups flour, cake mix, yeast, and salt in a large bowl; beat warm water into flour mixture until thoroughly combined. Mix remaining 1 cup flour into batter to make a soft dough.
Turn dough out onto a floured work surface and knead until smooth, 6 to 8 minutes. Roll dough into a 9x18-inch rectangle. Spread softened butter over dough and sprinkle evenly with sugar and cinnamon. Roll dough into a log, starting with a long edge, and pinch edges together to seal.
Preheat oven to 350 degrees F (175 degrees C). Grease a baking sheet.
Cut dough into 1-inch thick slices and arrange on prepared baking sheet. Cover rolls and let rise in a warm place until doubled, about 15 minutes.
Bake in the preheated oven until cinnamon rolls are lightly browned and cooked through inside, 15 to 18 minutes.
