The hack itself is safe, but theres alot of bans on BO2 because Treyarch has excellent anti-cheat when it comes to reports. You won't get banned because of the hack being detected, you'll get banned because someone from Treyarch reviewed footage of your games and saw you were walling/aimbotting.
My suggestion to you if you get the hack is to spend a few games with a friend 1 vs 1 so you can get footage of yourself and watch yourself hacking. See if you're doing anything obvious. You'd be surprised with what you're giving away. Do this and get good as being stealthy, and you can hack all you want with no fear of detection. Don't do this, and be following people through walls or snapping with the aimbot, and you'll easily get caught.