Preheat the oven to 350°F. Line two standard muffin tins with paper liners.
Whisk together the flour, sugar, cinnamon, baking soda, and salt in a medium bowl.
Beat the vegetable oil, pumpkin, and eggs in the bowl of an electric mixer on medium speed for about 2 minutes, until well combined. With the mixer on low speed, add the flour mixture in three additions, blending until just incorporated.
Using an ice cream scoop, scoop the batter into the muffin cups. Bake for 20 to 24 minutes, until a cake tester comes out clean. Remove from the oven and let cool for 10 minutes. Transfer the cupcakes to a wire rack and let cool completely.
Beat the butter and cream cheese in the bowl of an electric mixer on medium speed for about 2 minutes, until light and fluffy. With the mixer on low speed, add the powdered sugar, a little at a time, blending until well incorporated. Add the vanilla extract and salt and mix until smooth.
Spread a generous amount of frosting on top of each cupcake.