Cryptocurrency fund manager Alistair Milne participated in a challenge game organized by Bitcoin developer, after 1 trillion attempts, broke the Bitcoin wallet and obtained 1 BTC.
Alistair Milne, chief investment officer of the cryptocurrency fund Altana Digital Currency Fund, has created a challenge game on Twitter where the winner will take all Bitcoin. Starting in May, Milne periodically published clues for 12-word recovery phrases from a wallet address with 1 BTC. Contestants could reach the wallet’s recovery words with these clues so that they could attract Bitcoin to their wallets.
Milne wrote that she plans to give the last three or four words at once. He was doing this to prevent someone from opening the address with a brute-force attack. This attack expresses the method of trial by constantly guessing the words until you find the right combination. However, Milne’s plan didn’t work.
John Cantrell, the developer of Lightning Network’s messaging protocol Juggernaut, managed to break the Bitcoin wallet and got $ 9400 worth of Bitcoin. Cantrell was able to guess the remaining words with just eight words, found the right combination and opened the wallet. According to Cantrell’s post on Medium, there were about 1.1 trillion possible combinations that needed to be checked with eight words. The developer of Bitcoin, who wrote a special program for this, understood that the hardware used after running the program would not be enough. Cantrell’s laptop was able to control about 1250 combinations per second. So 108 million per day. It would take about 25 years to try the 1.1 trillion possibilities.
The developer, who tried cloud computing services to solve the problem, hired a GPU marketplace and several dozen graphics cards at Microsoft’s cloud computing service Azure. After everything was ready, he got to work. Meanwhile, Milne had published the eighth word. The system he created could try about 40 billion possibilities per hour. It reached Bitcoin in approximately 30 hours after 1 trillion attempts. He paid a $ 94 BTC transaction fee of $ 94 to quickly transfer the money to his wallet. He did this, taking into account the possibility of someone else reaching a solution.
Should you worry about your bitcoins?
If Milne had not released 8 words from the 12-word recovery phrases, it would have been impossible for such an attack to succeed. Today, especially in commonly used hardware wallets, 24-word recovery expressions are used, not 12-words. So the lottery is more likely to hit you several times in a row than these wallets being hacked by guessing the words of recovery.