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Ethernaut Lvl 5 Token Walkthrough: How to abuse arithmetic underflows and overflows

This is a in-depth series around Zeppelin team’s smart contract security puzzles. I’ll give you the direct resources and key concepts you’ll need to solve the puzzles 100% on your own.

Integer Overflow and Underflows

Detailed Walkthrough

contract Telephony {Telephone public phone = Telephone(YOUR_INSTANCE_ADDR_HERE);
//TODO...
}
function changeOwner(address _owner) public {
phone.changeOwner(_owner);
}

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