Break Into Zip File To Extract Bitcoins

Security researcher was asked to break into an old zip file. Inside the file he found something pretty amazing…

Once in a while we run into stories of very “talented” people manage somehow to lose a great fortune of digital currencies – It can be a BBC reporter who lost 25,000 pounds, a Youtuber who lost digital currencies in a total value of 2 million dollars (?!) or even cryptocurrencies trading stations that got hacked and lose 540 million dollars in a blink of an eye. These stories ends the same way, but not for this security researcher.

About 19 years ago, Michael Stay released a paper about hacking encrypted Zip files. Since then, Stay managed to work as a security researcher in Google and to became a CTO for a Startup company he started. But 6 month ago, he was approached on Linkedin by a Russian man. This man bought Bitcoin back in 2016 and payed $10,000. The key to his digital wallet he encrypted in a Zip file with a simple password.

As you may guess… He forgot that password. Today this digital wallet contains Bitcoin that worth over $300,000.

This man asked Michael if he could break this zip file and Stay replay that this process might take up to a year and will require equipment that is worth $100,000. The Russian man accepted the costs.

Stay was happy to know that the man kept the computer that the zip was encrypted from and the encryption mechanism is Zip 2.0, which is few decades old. These 2 factors help Michael to reduce the number of password combination to Quintillion – this huge number is 1 followed by 18 zeros…

For 4 month Stay and his partner developed a hacking attack to break the password and after its development, he ran the attack from server farm with Nvidia graphic processors. The attack run for 10 days and failed. But after a deep dive into the code, Stay found his bug, fixed it and the password was hacked in a day!

Michael said the the cost of this process was way less than $100,000 but the man was so happy that the process took less than 6 months and cost less than expected so he gave them a fat bonus.