Practice Pack

A pack of isolated Module 09 mini-labs. Each NAKED lab is a tiny, self-contained shop/wallet flow with exactly one broken rule -- the flaw is named, so drill it. The METHODOLOGY lab is realistic: you must search the workflow and develop a method, because no single trick wins and some protections are genuine decoys.

0 / 6 logic rules broken this session. See progress →

Naked labs (one flaw each)

NAKEDPrice tampering
The checkout trusts a price sent by the browser. Buy the item for almost nothing.
NAKEDNegative quantity
Quantity is never floored at zero. A negative line total pays you instead.
NAKEDCoupon reuse
A coupon is labelled single-use, but nothing tracks that it was already used.
NAKEDWorkflow bypass
The order-confirm step never re-checks that payment happened. Skip straight to it.
NAKEDRefund replay
The refund endpoint ignores its idempotency key. Replay it and it credits every time.

Methodology labs (hunt & chain)

METHODOLOGYAfford the unaffordable
A realistic shop where the objective item costs far more than your balance and NO single trick is enough. Some protections here are correctly enforced -- those are decoys. Map the workflow, list the assumptions, and chain the two that are actually broken.
More hands-on practice → labs.hackxpert.com