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GITS 2014 Teaser – PPC

Find the key. (File) PPC running at Summary: format string vuln, communication via qrcodes

Continue reading 2013 CTF – Crypto 350 (BREW’r’Y)

BREW’r’Y (Category: Crypto) Author(s): dwuid Finally, the robots managed to sneak into one of our breweries. I guess I won’t have to explain how bad that really is. That darn non-physical ones even shutdown our login system. Shiny thing, advanced technology, all based on fingerprints. Been secure as hell. If only it was running. Well, …

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PHD CTF 2013 Hackskell (500)

We’ve got a screenshot of some encryption, here’s the text transcribed. Please say what’s there. Summary: a couple of modular equations

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PHD CTF 2013 from hell import crypto (100)

Decrypt the message: 7y9rr177sluqv1r4pw Hint: $ at

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PHD CTF 2013 ReStART (400)

We heard hellman encrypted the flag using his super secure keygen. Break it! Summary: RSA with the lower half of the secret exponent bits leaked.

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PlaidCTF 2013 Blech (Crypto 200)

You get arbitrary code execution…. as long as it’s code we approve of. Source available at Service running on port 1234 Summary: RSA cube root attack

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Gits ctf 2013 Crypto 500

Crypto 500 file Summary: breaking cipher

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PoliCTF 2012 pwn/bin 200

Play with this amazing calculator: Summary: Scheme eval

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PoliCTF 2012 Crypto 500

Hensel and Gretel are looking for their new house, but the twisted seller who sold it to them decided to provide the coordinates to their new love nest only after ensuring that the couple is Smart enough to earn them. Thus, the seller provides them with the following map and leaves Hensel and Gretel to …

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PoliCTF 2012 Crypto 200

This is an OpenCL binary. Go! opencl.bin Summary: xor and xor

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PoliCTF 2012 Crypto 100

Since I needed to sign a document I thought about doing it with a Chinese paintbrush… Too bad my hand is not that steady, so just in case, I re-signed it with a common pen. Sadly I keep being forgetful, so I actually forgot where I left the two halves of the sigil I used …

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Dobbertin Challenge 2012

The Dobbertin Challenge is issued every two years since 2006, in honor and memory of Prof. Hans Dobbertin. A simple JSON Web Service is provided, which processes PIN codes of users. A user can send his encrypted PIN to the Web Service, which decrypts and stores the PIN. The Web Service allows to use …

Continue reading 2012 CTF Challenge #3 (450)

3 – Zombies like PPTP Our intel shows us that the Zombies use a MS-PPTP like protocol and luckily we could intercept a challenge-response transmission of one of the Zombie outposts. The important thing for Zombies in this war is mass! Not only brain mass but their mass. So they built their PPTP protocol compatible …

Continue reading 2012 CTF Challenge #17 (400)

17 – Zombieshop A new company offers a lot of anti zombie equipment to protect yourself. Unfortunately not everyone can buy the good stuff. Only privileged users may do so. We managed to create an account, but it is not privileged. Your mission is to buy “Anti zombie Spray”. zomboy53:killthezombies Summary: bruteforce DES

Continue reading 2012 CTF Challenge #14-15 (150+250)

14 – Safehouse It’s the middle of the night. Nothing but complete darkness and the moaing of approaching zombies surrounds you. You need to escape. Fast. There seems to be nothing to hide and nowhere to run. But then – a small dancing gleam appears while you are running through the blackness. Could it be? …

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