picoCTF 2019 vault-door-1 Writeup

vault-door-1 is a Reverse Engineering challenge worth 100 points.

Its description is:

This vault uses some complicated arrays! I hope you can make sense of it, special agent. The source code for this vault is here: VaultDoor1.java

A Java source file is provided, named VaultDoor1.java. This challenge was straightforward. Reading the source showed a silly comment and the scrambled password:

I solved this with a one-liner in my shell:

 % grep charAt VaultDoor1.java |sort -V |awk {'print $3'} |tr -d "\'\n"

One thought on “picoCTF 2019 vault-door-1 Writeup

  1. Pingback: picoCTF Writeups – DMFR SECURITY

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