October 2016 archive

hack you spb @ 17 Oct 2016

Remember hack you CTF? Yeah, that random event that we throw for our freshmen and everyone interested. We’re hosting a new one. It’s fall already and that means the new CTF season is starting, and so is the new academic year in the universities. This is the time when we want to attract more freshmen …

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HITCON CTF QUALS 2016 – Reverse (Reverse + PPC 500)

At least our ETA is better than M$. http://xkcd.com/612/ reverse.bin Summary: optimizing an algorithm using Treap data structure and CRC32 properties.

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HITCON CTF QUALS 2016 – PAKE / PAKE++ (Crypto 250 + 150)

pake1.rb pake2.rb Summary: attacking password-based key exchange schemes based on SPEKE with MITM.

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TUM CTF 2016 – Shaman (Crypto 500)

Oh great shaman! Somehow the village idiot got his hands on this fancy control machine controlling things. Obviously, we also want to control things (who wouldn’t?), so we reverse-engineered the code. Unfortunately, the machine is cryptographically protected against misuse. Could you please maybe spend a few seconds of your inestimably valuable time to break that …

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TUM CTF 2016 – Tacos (Crypto 400)

All my fine arts and philosophy student friends claim discrete logarithms are hard. Prove them wrong. nc 104.198.63.175 1729 vuln_tacos.py Summary: bypassing Fermat primality test with Carmichael numbers and solving discrete logarithm using Pohlig-Hellman algorithm.

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TUM CTF 2016 – ndis (Crypto 300)

We have a HTTPS server and client talking to each other with you right in the middle! The client essentially executes curl –cacert server.crt https://nsa.gov with some magic to redirect the transmitted data to your socket, to which the server responds with a lovely German-language poem. NOTE: There is nothing else hosted on the server; …

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