Hacking Series Part 20

Challenge: Holiday Hack Objective 11b

Category: pwn?? blockchain??

We are given part of a blockchain and told there is an altered block somewhere. The goal was to find the four altered bytes in the new block and change it back to their original values, or essentially, reproduce the original block. In the objective description, there was a SHA256 of the changed block which is the only indication of what block we should be looking at.

I ran a Python script to iterate through all the blocks until I found the one with the matching SHA256. I…

--

--

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store