Paper 2012/588 Original: eprint.iacr.org/2012/588 ↗
Breaking Public Keys - How to Determine an Unknown RSA Public Modulus
Abstract
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.
Metadata
- Available format(s)
PDF- Category
- Public-key cryptography
- Publication info
- Preprint.
- History
- 2012-10-25: last updated
- 2012-10-25: published
- Short URL
- https://ia.cr/2012/588
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2012/588,
author = {Hans-Joachim Knobloch},
title = {Breaking Public Keys - How to Determine an Unknown RSA Public Modulus},
howpublished = {Cryptology {ePrint} Archive, Paper 2012/588},
year = {2012},
url = {https://eprint.iacr.org/2012/588}
}