Cashio Exploit Workshop

The Cashio hack was one of the biggest hacks occurred in Solana ecosystem which allowed the attacker to print infinite amount of $CASH with a faked collateral. This repository provides a local environment that you can try writing your own attack for Cashio. This exploit workshop is influenced by Solana Security Workshop which we highly recommend to finish before trying this one.

DISCLAIMER: This tutorial is provided entirely for an educational purpose. We DO NOT endorse or support any type of illegal activities.

Steps

1. The main file you will be working on is poc/src/main.rs. The file contains the code that prepares the mock environment with a real Cashio bank filled with assets. Take a look at the provided code to learn how to use the provided LocalEnv struct.
2. Write your PoC in execute_poc() function. Your goal is to write code that exploits a logic bug in the Cashio contract that allows you to print infinite amount of $CASH and use the printed $CASH to steal collaterals (Saber LP token) stored in the bank.
3. Run make to check your answer. After the initial build of dependencies cargo run also works.

Hints

• Cashio attack analysis by Soteria
• You can check our model answer under poc branch

Who are we?

We are Pwned No More, a white hat hacker DAO created by and for the best talents to protect our beloved crypto/Web3 world.