From now on, I will assume all my user-data will be compromised, we need a new way to store the user-data, it will be a balance of convenience and security, but

From now on, I will assume all my user-data will be compromised, we need a new way to store the user-data, it will be a balance of convenience and security, but more importantly, it needs to be temporal, i.e. the use-data shall not be static anymore, something like a virtual and temporarily generated password for each session?