[bingbingbing777]

Yes, the quality of the glass, number of lens elements, coating on the front element, internal reflections, aberrations and so on. It won't be affecting colors like red turns to blue, but more like red goes to a slightly different muted shade of red.

[guenthert]

To expand on this a little: there is no lens which changes the frequency of light. What happens that due to chromatic aberration structures in a given colour could be less precisely focused than others and in the blur a different mix of frequencies (different shade of colours) could appear.