It's a backdoor because it grants access (to new messages as well as any messages replayed) with explicit authorization by the application but without explicit

It's a backdoor because it grants access (to new messages as well as any messages replayed) with explicit authorization by the application but without explicit authorization by the user. That seems to fit the currently accepted understanding of the word: https://en.wikipedia.org/wiki/Backdoor_(computing) https://en.wikipedia.org/wiki/Backdoor_(computing)