Ethernaut Lvl 2 Fallout Walkthrough: how simple developer errors become big mistakes

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.

The Walkthrough

// Simply invoke this function with nominal ether
function Fal1out() public payable {
owner = msg.sender;
allocations[owner] = msg.value;

Real examples of such simple human errors

The Rubixi Bug

The Hackergold Bug

// do the actual transfer
balances[from] -= value;
balances[to] =+ value;



Engineer. Tweets @0xSage

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