Tags: ida pintool idapython 

Rating:

Wrote an idc script to analyze the pattern by decrypting the code, then wrote a pintool to calculate the flag based on the `and` conditions on different bytes.

![solution](https://gist.githubusercontent.com/sudhackar/ad9c15851f274b3248ef1645abee9ae8/raw/ce857ac93e1da9f3eecf80c76a68a05f4ad32020/zwiebel.png)

Original writeup (https://gist.github.com/sudhackar/ad9c15851f274b3248ef1645abee9ae8#file-zwiebel-cpp).