The shutter count will be stored in the camera's firmware / memory, so someone clever enough could probably edit it.
I've found a number of pieces of software which claim to be able to edit the shutter count - but fee to use it ranges from $ 30 for 5 days use to $ 750 per year. I'm not going to post links - but it didn't take long to find, and there was software to do same for Nikon as well. Could also be a scam / virus infected malware which you then have to spend more money to unlock the ransom demand.
I'm sure that official Canon tech's have the ability to do so as well.