Show HN: Portable Secret – How I store my secrets and communicate privately
This is password protected, so then an attacker must crack the password. The author exchanges the password over a phone call, which requires the password to be relatively weak, meaning the password is probably crackable.
Exchanging the password via a second channel that the other user can copy and paste a more difficult password from to decyrpt the document might be more secure. The password may be more exposed, but an attacker would have to compromise both channels. Basically use two messaging platforms (one of which could be email) ideally where at least one channel is sent encrypted. For example if the other party is using their mobile phone to view the payload they should have a messaging app to copy and paste from that is at least encrypted in transit if not e2e.