September 2016 archive

CSAW Quals 2016 – Broken Box (Crypto 300 + 400)

I made a RSA signature box, but the hardware is too old that sometimes it returns me different answers… can you fix it for me?} e = 0x10001 nc 8002 Summary: fault attack on RSA signatures, factoring using private exponent exposure.

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Tokyo Westerns/MMA CTF 2016 – Backdoored Crypto System (Reverse+Crypto 400)

Get the flag. bcs.7z $ nc 3971 Summary: recovering AES key from partial subkey leaks.

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Tokyo Westerns/MMA CTF 2016 – Pinhole Attack (Crypto 500)

Decrypt the cipher text with a pinhole. $ nc 23464 pinhole.7z Summary: attacking RSA using decryption oracle leaking 2 consecutive bits in the middle.

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