The Surreal Madness of Ethereum's Pyramid Schemes
medium.com
medium.com
> How?
> Because the developers of the OG contract had failed to use the safe math functions included in Solidity, the language of Ethereum’s smart contracts, this allowed an unknown hacker to make an unsigned integer underflow withdrawal — giving themselves an infinite number of PoWH’s tokens to withdraw, and draining the contract.
It is absurd that one needs to opt-in to unsigned integer underflow checking, especially in a language designed for writing financial contracts.