Hack.lu 2013 CTF Write-Up: Roboparty

Robot LHCH is happy. He made it into the castings for the tenth roman musical. He even is so happy that he went on the Oktoberfest to drink some beer. Unfortunately it seems that he drank too much so now he is throwing up part of his source code. Can you decipher the secret he knows?

Warning: Viewing this page is not recommended for people that suffer from epilepsy. We are dead serious.

And here is your totally eye-friendly challenge: https://ctf.fluxfingers.net/static/downloads/roboparty/index.html

The linked page provided a tripping psychedelic experience to our team. After connecting a laptop to the projector with the page in fullscreen mode, we spent half of the CTF partying hard.

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Hack.lu 2013 CTF Write-Up: What’s wrong with this?

We managed to get this package of the robots servers. We managed to determine that it is some kind of compiled bytecode. But something is wrong with it. Our usual analysis failed – so we have to hand this over to you pros. We only know this: The program takes one parameter and it responds with “Yup” if you have found the secret code, with “Nope” else. We expect it should be obvious how to execute it.

The challenge provides a compressed archive hello.tar.gz which contains a bunch of shared objects, an archive called library.zip (actually an ELF executable with an embedded ZIP) and a Python interpreter py. The executable to be cracked is hello, which will reply “Yup” if the correct flag is provided, “Nope” otherwise.

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Hack.lu 2013 CTF Write-Up: Robotic Superiority

Help us fight the evil robotic lieutenant Don Sim. He wants to spread robo propaganda to cover his actions on the Oktoberfest. But he needs good video footage for that. So he created an IRC bot that collects information about robots in movies. Robotic emancipation can NOT happen, you have to stop him! All we need is his private key. Our agents located the bot, here is all we know about it:

Server: irc://ctf.fluxfingers.net:1313
Bot: lib[1-5] (load balancer)
Key: /var/private/key.txt

Hint: All available commands are listed with “help”. 3 connections allowed per ip.

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PlaidCTF 2012 write-up: The Game

The following description is provided:

Robots enjoy some strange games and we just can’t quite figure this one out. Maybe you will have better luck than us.

The game offers a choice between two hex strings asking for the “bigger” one. Anyway, it doesn’t appear to be a way to determine which one is bigger just by looking at the values.
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Hack.lu 2011 CTF Write-up: Unknown Planet

This week we participated in the Hack.lu 2011 CTF, a Capture-The-Flag event organized by the FluxFingers team at Hack.lu. Even if we were only three with two other members playing at night, we placed 6th out of >100 teams! Congrats to FluxFingers for the wonderful work done, we enjoyed it so much.

This is our first write-up for this CTF, hopefully more will come.
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