A simple introduction to the format string family of vulnerabilities. These let you read and write memory in fantastic ways.

Problem can be found in

    /problems/format_2_358e7afd8b3804d8

    on the shell machine, binary downloadable here[1] source here[1].

    Hint: The trick here is to overwrite one of the entries in the global offset table 

    [1]https://2013.picoctf.com/problems/format2
    [2]https://2013.picoctf.com/problems/format2.c