[<prev] [next>] [day] [month] [year] [list]
Message-ID: <CAPcZBq6kE2r-_-XKy22dNsbcKjjds=d2b=kBpMprN84oV63r_Q@mail.gmail.com>
Date: Thu, 10 May 2018 23:56:15 +0800
From: Qinghao Tang <luodalongde@...il.com>
To: oss-security@...ts.openwall.com
Subject: erc20 contract KoreaShow bug
An integer overflow in the transferMulti function of a smart contract
implementation for KoreaShow, an Ethereum ERC20 token, allows attackers to
accomplish an unauthorized increase of digital assets via crafted _value
parameters.
------------------------------------------------------------
Let`s see where this issue is:
function transferMulti(address[] _to, uint256[] _value) public returns
(uint256 amount){
require(_to.length == _value.length);
uint8 len = uint8(_to.length);
for(uint8 j; j<len; j++){
amount += _value[j]; <------here, crafted _value can make
amount overflow
}
require(balanceOf[msg.sender] >= amount);
for(uint8 i; i<len; i++){
address _toI = _to[i];
uint256 _valueI = _value[i];
balanceOf[_toI] += _valueI;
balanceOf[msg.sender] -= _valueI;
Transfer(msg.sender, _toI, _valueI);
}
}
---------------------------------------------------------------
If you can reproduce the issues , please give it a cve id ,and disclosure
this vulneralbility officially claiming that " Qinghao Tang " is the
discoverer .
Powered by blists - more mailing lists
Please check out the
Open Source Software Security Wiki, which is counterpart to this
mailing list.
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
