Nuit du Hack CTF Quals // Matryoshka Stage 2 // Keygenning with KLEE and Hex-Rays (100 Points)
Capture the Flag, Nuit du Hack CTF Quals May 8, 2016First, we need to identify the code that handles validating passwords. Opening the binary in IDA Pro makes it quite easy to visualize the main function.
Understanding all of the instructions isn’t required; it’s clear that the left branch occurs (outputting Usage: %s <pass>) when no input is give and the middle branch happens when an incorrect password is given (outputting Try again...… Read more