The hotel check-in trick Imagine you walk up to a hotel front desk, pick up the paper check-in form, and fill it in normally: your name, check-in date, number of guests, room type: Standard. But before you slide it back across the counter, you quietly pencil in one more line — room type: Preside...
Source: [Dev.to](https://dev.to/khuepm/the-hotel-upgrade-hack-mass-assignment-vulnerabilities-in-apis-3h62)