Actually, light is bent by all things that have mass. It is so small it is undetectable though. For objects the size of galaxies, or even stars, though, experiments have been done to prove that light is bent by massive objects. Gravitational lensing is what this effect is called.
Although we use it to detect dark matter, an experiment using the sun to predict the position of another star blocked from our line of sight from the sun has been conducted numerous times, concluding each time that light from the star is bent by our sun.