works side and front, some traps

If you focus on keeping your shoulders from shrugging and squeeze your shoulder blades together towards the top of the movement, it's a pretty effective way to work the medial and rear part of your delts

Depending on how you do upright rows you can hit your shoulders or back more.... If you bring your elbows past shoulder level you hit your traps more. Same goes for shoulder raises in general. Great exercise though. It works your core too so remember to keep everything tight! Cheers.

If you do your upright rows with a close grip, and you pull the weight to your chin, keeping your elbows aligned with your shoulders it's going to work the front delt and the traps and your rear delt. Instead, if you do your upright rows with a very wide grip (forearms making an angle of 90 degrees with the upperarm) and pull the weight to your lower chest (don't forget to keep the weight close to your body), you are going to focus on the side delts. =) (sorry for my english I'm french)

Upright rows are not very good for your rotator cuff, don't do them. There are better exercises that you can utilize instead.