Tag: crt

PlaidCTF 2016 – Radioactive (Crypto 275)

We just got this fancy new cryptographic device and it seems to work great… for the most part. But sometimes the values it gives me are wrong. Maybe you could take a look for me. radioactive.tar.bz2 Summary: fault attack on RSA signature (not RSA-CRT)

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0CTF 2016 Quals – RSA? (Crypto 2 pts)

It seems easy, right? rsa.zip Tip: openssl rsautl -encrypt -in FLAG -inkey public.pem -pubin -out flag.enc Summary: factoring 300-bit modulus into 3 primes, extracting cube roots.

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MMA CTF 2015 – Motto Mijikai Address (Crypto/Web 100+300)

Login as admin and get the flag1. mmaddress.7z Summary: breaking HMAC-CRC512

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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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hack.lu CTF 2011 Wipe out the Klingons (400)

Category: crypto We already made it. The evil Klingons agression is nearly fended. But their final mothership is well protected and even sacrifing a huge number of battleships caused only minor damage. Spies told us an unclear message caused most technical operators and the commander to leave the ship. Unfortunately we are unable to locate …

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