The Value Overflow Incident in the Bitcoin Blockchain — 15th August, 2010

Jean Cvllr
2 min readAug 30, 2018


The biggest bitcoin hacked happened in… 2010 !

In the public realm, Blockchain is synonym of “digital fortress”. However, it was not the case in the early days.

One of the most striking security issue in the blockchain space happened the 15th of August 2010 in the Bitcoin Blockchain. What happened exactly ?

A transaction created 184,467,440,737.09551616 bitcoin out of thin air !

It was shocking at that time, especially when you consider that there is a limit of 21 millions bitcoin that will be created on the network, according to the sofware rules.

At that time, the protocol developers deployed a soft fork to fix the bug. A new version of the client was published within five hours of this discovery. The network solved this crisis by regorging the transactions that created those bitcoins out of thin air out of the network.

You can see the changes in the Bitcoin source code here

The soft fork implemented a new consensus rule that rejected output value overflow transactions.

This problem happened at block height #74638

Before to dive more into the understanding of this issue and write more about it, I leave you with further readings:

A good pdf about blockchain security issues :



Jean Cvllr

Smart Contract engineer at @LUKSO. Full Stack Developer.