Is it possible to disclose personal data in VK?

Question

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Good afternoon. I am interested in such a question, is it possible to read someone's private messages, some other personal data by adding an application to VK?
For example:
I downloaded an application called N and decided to log in through VK, so in order to accept consent, a message pops up on the screen saying that they say that private messages, friends, and so on will be opened to that application. So the same developer of that application, can he somehow read private messages?
Thank you in advance.

Answer 1

Do you want to steal someone's personal data?

Answer 2

Audio, video is possible, but unfortunately there is no message