This became too long for me to grammar and spell check... apologies in advance.

If you are talking about raining satellites down on earth, rods from god style, than I can assure you the risk is theortic at best.

Lets, as it's said, start from the beginning. In order for a satellite to hit the surface of earth, it has to be big enough, massive enough and dense enough. Not a lot of satellites are in that category. probably non that can be turned into a proper kinetic energy weapon.

Then it needs the right trajectory. Too shallow and the speed fall will be gradual, the satellite will break up to small bits that will, in the worst case, fall out of the sky in their respective terminal velocity. Too steep of a trajectory and it will burn it's self completely.

Now lets say we have the perfect satellite and the perfect trajectory for reaching the target, on top of it being vulnerable to cyber attack. We reach the biggest hurdle - fuel. Satellite don't carry as much as you might think. The stuff is heavy and expensive. Satellites will typically use a lot of their fuel in their initial orbit insertion or will carry only what is needed to keep their said orbit as long as their mission dictates. Why is that important? because big changes in a satellite orbit are very costly in terms of energy, i.e. fuel.

Ok, ok, lets pretend we have a satellite with all the above criteria and has enough fuel. Now we need to make the manoeuver. oops, the satellite engines can't make it in one go. see, satellites use small thrusters to do most of their manoeuvring, as they mostly do station keeping or small orbital changes. So now we're talking about a series of maneuvers in order to carry out the deadly plan. and do it without the original owners getting control back.

But what if it did happen, you ask. Then I have more bad news. The satellite will be tracked, it's trajectory calculated and a warning would be issued. The damage would be light, but will generate lots of headlines.