How to use Flask's SECRET_KEY to send own information to the server via session?

Question

Data protection

Challenge with hackthebox. You need to somehow send data through the session so that in the code they are retrieved using session.get('key1').
I know, there is a video with a solution to the problem, but I would like to understand how to get to this solution myself ...

Answer 1

drive debugging, you will understand where the key is used,
change it