The problem is that you cannot add a hardware random number generator to existing machines and the cost of buying a new machine is high enough that casinos do not want to do it.
If the scammers get too big the casinos will replace the compromised machines and the scam ends. The scammers seem to know this: they are targeting more an more casinos around the world in an apparent effort to make sure it is worth the risk.
Actually you don't need hardware random number generators. There is enough variance in human input to feed a cryptograhic random number generator. The code to add this probably wouldn't be that hard to write (they might be 8 bit CPUs or some such limit that makes it impossible though). However all code changes have to be certified by regulatory bodies (for good reason) which makes it not worth the effort to fix old machines.
That is fair enough. For older machines I have no idea what the answer is. I just mean designing this securely is not too hard. Hardware RNG is cheap, though. You are right though, these old machines do present a pickle.
If the scammers get too big the casinos will replace the compromised machines and the scam ends. The scammers seem to know this: they are targeting more an more casinos around the world in an apparent effort to make sure it is worth the risk.
Actually you don't need hardware random number generators. There is enough variance in human input to feed a cryptograhic random number generator. The code to add this probably wouldn't be that hard to write (they might be 8 bit CPUs or some such limit that makes it impossible though). However all code changes have to be certified by regulatory bodies (for good reason) which makes it not worth the effort to fix old machines.