Juniors CTF - 400 - Dirty Repo - Forensics

Information#

Version#

By	Version	Comment
Chill3d	1.0	Creation

CTF#

• Name : Juniors CTF 2016
• Website : juniors.ctf.org.ru
• Type : Online
• Format : Jeopardy
• CTF Time : link

Description#

categories: admin, forensics

Gruncle Stan loves money very much and doesn't shun to use unacceptable tricks to get it. Not so far he started a new project with an aim to embezzlement of public funds. He hired some developers and decided to "borrow" source code. But one liberal-minded young man didn't like, that Stan's project is a plagiarism. This zealous fighter for justice decided to spoil one developer's project. Try to find out, what the malefactor added.

Here are all developers' projects -> WORKDIRS

Solution#

In this challenge, we get a tar.gz file. In it, there are 20 tar.gz files containing git repo from openvpn.
So first, I unzip all tar.gz file, and I seek so differences between repos :

$ diff -r comp_1 comp_2
Binary files comp_1/openvpn/.git/index and comp_2/openvpn/.git/index are differents
$ diff -r comp_1 comp_3
$ diff -r comp_1 comp_4
$ diff -r comp_1 comp_5
132a133
> //FLAG -> gRunCle_StAn_tHe_woRsT_coDeR

Flag : gRunCle_StAn_tHe_woRsT_coDeR