depends. where law hasn't become agressive enough to prosecute plain reverse engineering it isn't rare for such cases to be made as copyright infringement. what jusrisdiction would hypothetically apply here ... i have no idea.A program that modifies values saved in your computer's RAM isn't copyright infringement.
cheating in a game is of course no crime in any country/state i know of. unless you also show your genitals, or rip off people, or blaspheme or something
also, everyone on the internet has a lawyer, didn't you know?