It seems to me, that if there are vulnerabilities or potential backdoors, the incentive would be huge for hackers and coders to find these vulnerabilities and exploit them.
There is no backdoor in the official version of the program as far as I know. Only the Gestapo/NKVD will be allowed to fully access to your digital information. Little swindlers will not.
good thing bitcoins can't be turned off by deactivating a chip...
It's only a matter of time. When the world accepts the cashless system you will be required to wear GPS/Cell tower trackable chip which will be always with you and always online connected to the supercomputer.