Tag: discrete logarithm

Google CTF 2017 Quals – BLT (Bleichenbacher’s Lattice Task – Insanity Check)

A slow descent into the dark, into madness, futility, and despair. BLT.jar (not necessary) STDOUT Flag.java Summary: DSA with short secrets, lattice + meet-in-the-middle attack.

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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 1729 vuln_tacos.py Summary: bypassing Fermat primality test with Carmichael numbers and solving discrete logarithm using Pohlig-Hellman algorithm.

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Olympic CTF 2014 GuessGame (300)

Be careful, it’s cheating! nc 3126 Summary: discrete logarithm with group oracle

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