Paper 2000/061 Original: eprint.iacr.org/2000/061 ↗
RSA-OAEP is Secure under the RSA Assumption
Abstract
Recently Victor Shoup noted that there is a gap in the widely-believed security result of OAEP against adaptive chosen-ciphertext attacks. Moreover, he showed that, presumably, OAEP cannot be proven secure from the {\it one-wayness} of the underlying trapdoor permutation. This paper establishes another result on the security of OAEP. It proves that OAEP offers semantic security against adaptive chosen-ciphertext attacks, in the random oracle model, under the {\it partial-domain} one-wayness of the underlying permutation. Therefore, this uses a formally stronger assumption. Nevertheless, since partial-domain one-wayness of the RSA function is equivalent to its (full-domain) one-wayness, it follows that the security of RSA--OAEP can actually be proven under the sole RSA assumption, although the reduction is not tight.
Metadata
- Available format(s)
PDF- Category
- Cryptographic protocols
- Publication info
- Preprint.
- History
- 2001-05-29: last updated
- 2000-11-27: published
- Short URL
- https://ia.cr/2000/061
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2000/061,
author = {Eiichiro Fujisaki and Tatsuaki Okamoto and David Pointcheval and Jacques Stern},
title = {RSA-OAEP is Secure under the RSA Assumption},
howpublished = {Cryptology {ePrint} Archive, Paper 2000/061},
year = {2000},
url = {https://eprint.iacr.org/2000/061}
}