Breaking Public Keys - How to Determine an Unknown RSA Public Modulus

نویسنده

  • Hans-Joachim Knobloch
چکیده

Not surprisingly, the common use of any public key crypto system involves publishing the public key and keeping the private key secret. There are however a few applications where both the private and public key are kept secret, thereby effectively converting a public key crypto algorithm to a symmetric algorithm. We show that if the RSA cryptosystem is used in such a symmetric application, it is possible to determine the public RSA modulus if the public exponent is known and short, such as 3 or F4=65537, and two or more plaintext/ciphertext (or, if RSA is used for signing, signed value/signature) pairs are known.

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عنوان ژورنال:
  • IACR Cryptology ePrint Archive

دوره 2012  شماره 

صفحات  -

تاریخ انتشار 2012