Medium
Business Logic Flaws
CouponCart checkout (business logic)
A discount coupon meant to be used once can be stacked until the order is free.
PentestingHere Academy
Official Academy lab
- Attempts
- 5
- Solves
- 5
- Published
- 6 Sep 2026
Scenario
CouponCart sells a Pro License for $100. There is a promo coupon, SAVE10, that takes a
little off the total.
Goal
Drive your order total to $0 (or below) and complete checkout. The "fully comped" receipt prints a fulfilment code, submit it as the flag.