That’s a Qi charger; it has no software/firmware embedded. Additionally, there is no data transfer over the wireless charging. Yes, there is power negotiation, but your phone cannot receive data nor send data over the charging coils.
it looks like someone is controlling the phone remotely
There is an easy way to test this: put your phone in Airplane Mode prior to placing it on the charging base. Since the base has no way to communicate to the outside world, any scrolling you now observe will be local meaning *it’s not being remotely controlled.
What could it be?
Remember, your screen is capacitive meaning a slight electrical field could cause your screen to respond. Your Apple Watch, if unlocked, can unlock an iPhone in proximity; move your Apple Watch to verify. Also move the charger to verify it’s not interfering.
Finally, the behavior you’re seeing is not “hacking.” Hackers don’t do what they do to scroll your screen. They plant apps and malware to steal your data or use your devices an attack vector. Scrolling screens is a waste of time and alerts you to their presence; the last thing a hacker wants.