Preheat your oven to 350°F (175°C) and prepare a 9x13-inch baking pan by greasing it thoroughly. In a mixing bowl, combine the white cake mix, eggs, water, and vegetable oil as per the package instructions. Stir until smooth and lump-free. Pour the batter into the prepared pan and bake for 25 to 30 minutes, or until a toothpick inserted in the center comes out clean. Allow the cake to cool in the pan for 10 to 15 minutes.

While the cake is baking, prepare the cranberry layer. In a medium saucepan over medium heat, combine the cranberry sauce, 1/2 cup water, and granulated sugar. Stir until the mixture is well blended and slightly thickened. Remove from heat and allow it to cool for a few minutes.

Once the cake has cooled, use the handle of a wooden spoon or a straw to poke evenly spaced holes across the surface of the cake, about 1 inch apart. Pour the warm cranberry mixture over the cake, ensuring it seeps into the holes and spreads across the surface. Let the cake cool to room temperature, then transfer it to the refrigerator and chill for at least 2 hours to allow the flavors to meld.

In a separate bowl, mix the whipped topping with the vanilla extract until combined. Spread the topping evenly over the chilled cake, creating a smooth and creamy layer. Slice into squares and serve cold for a delightful holiday dessert.