webmedium

Coins

alfactf

Task: Web shop with JavaScript/Node.js backend where user controls divisor in price calculation. Solution: Exploit division by zero (1/0 and 1/-0) to create Infinity values, then combine them to get NaN balance which bypasses all comparison checks.

$ ls tags/ techniques/
shopnodejsjavascriptnaninfinitytype_coerciondivision_by_zeroinput_validation
NaN balance manipulationDivision by zero exploitationJavaScript comparison quirks
🔒

Permission denied (requires tier.pro)

Sign in to access full writeups

Create a free account with GitHub, then upgrade to Pro.

$ssh [email protected]