First Flight #1: PasswordStore

Hacker can retreive password using only the contract address and slot.

Every variable on smart contracts is visible, even if we set that as private.
We can do this by working with contract slots.
Slots rappresent the storage of every variable in a smart contract.
Every slot can store 32 bytes of memory.
Slots are accessible from everyone and data are not encrypted.

There is even one more error.
Anyone can change password.

Sensitive on-chain data, Access Control

High Level

Hardhat, ethers.js

Sensitive data should not be stored in the blockchain and Access Control is required for sensitive functions.