AngstromCTF_2018: slots

Category: Misc Points: 90 Description:

defund is building a casino empire. Break his slot machine, which is running at web.angstromctf.com:3002. Note: connect with netcat or an equivalent tool.

Write-up

This challenge is a mere teaser on one of Python's quirks with integers, that it could be NaN or not a number. If it is not a number, it simply cannot be used to check if it's below 0, above money or 1000000000. As such, we can break this challenge with just one bet.

$nc web.angstromctf.com 3002 Welcome to Fruit Slots! We've given you$10.00 on the house.
Once you're a high roller, we'll give you a flag.
You have \$10.00.

Therefore, the flag is actf{fruity}.