Not really. That is what makes these systems fairly safe and secure. For the most part you really cannot easily "hack" a CAN system. You need to be tapped into the twisted pair wires (bus) and you can only issue updates to modules limited to the design of the module itself. The modules can be re-flashed with new code base (added features), but that is not something that is normally done.
Do you actually us your PTT button for it's intended purpose? If not (like me) I can use the button actions to do other things (like operate my CC)
Well, the PTT button on the same side as the throttle is
UNsafe in my opinion - yes, I use it for its intended purpose, and if you are trying to, for example, get instructions to or from another bike in heavy traffic in an unfamiliar location, using it is a nightmare. Goodness knows what possessed HD to switch them round like that. Cruise is the less frequently used button, and having it near the throttle makes sense. Trying to hold a PTT button in while managing the throttle is just lunacy.