Hack.lu Writeups

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2012 CTF by Fluxfingers

It was again a great moment of fun to participate to this year's CTF organised by Fluxfingers @ Hack.lu 2012

T-Shirt contest

This one is quite apart from the other challenges for several reasons:

  • The challenge was actually printed on participants' t-shirts, as of last year
  • Surprisingly enough, only 2 teams over the 290 who scored at least one challenge managed to solve it!! (none of the top 10, they were teams #50 and #83)
  • The challenge was the only one not designed by Fluxfingers team but... by myself, with the help of Alex to design the actual T-Shirt

Still I played the ctf fairly, proof is that even my team (woyouyizhixiaomaol=我有一只小毛驴) didn't find the solution ;-)
I must admit, the challenge was easier for local people than for remote people, reason is that a list of words was written on the T-Shirt while online a patchwork of unrelated images was visible.
On first evening, as no one solved it yet, we added an extra hint in the challenge description.
On last morning, as no remote team managed to solve it, we also published a picture of the T-Shirt for remote teams. Apparently it didn't help...
Here is it:

28 - T-shirt
Same as local T-shirt challenge: https://ctf.fluxfingers.net/challenges/noclue.png 
Send your answers to (masked email on this wiki as it's too late and we hate spammers)
Hint: "It was in use sometime ago" #ctf #infosec 
Hint: https://ctf.fluxfingers.net/challenges/IMG_4924.JPG

Here is noclue.png:

Hacklu2012 Noclue.png

Each element represents one word. Maybe you don't guess the exact right word for each of them, maybe not exactly in the right order, but it doesn't really matter as with a few words, it's enough to find the trick as we will see later.
So if we do the exercice we get something like:
RJ45? / unicode / crypta / assyria? / creatrix / ochra / chimaera / cumulate eucrite / jana antepono / condoleo / remissus / Πελασγοί=pelasgoi / antepono / cimex lectularius
First two seems to refer to known technologies while all the rest seems mostly latin words

Second image is the T-Shirt itself and there you get the exact word list:

Hacklu2012 IMG 4924.png

So actual word list is:
utp cable unicode crypta assyrius creatrix ochra chimaera cumulate antepono condoleo remissus pelasga antepono cimex