i dont think so.
Is it possible for someone else to access…
Why are you even asking? The answer is “Yes.”
Repeat after me, anything can be hacked
There is a difference between Hacking the software and trying and breaking the encryption and gaining access to the pictures.Passwords can be guessed / Storage chips can not be encrypted. As for back door without having to break encryption…. a very slim chance.
With the right tools and knowledge anything is possible.