Paper 2006/223
What Hashes Make RSA-OAEP Secure?
Daniel R. L. Brown
Abstract
Firstly, we demonstrate a pathological hash function choice that makes RSA-OAEP insecure. This shows that at least some security property is necessary for the hash functions used in RSA-OAEP. Nevertheless, we conjecture that only some very minimal security properties of the hash functions are actually necessary for the security of RSA-OAEP. Secondly, we consider certain types of reductions that could be used to prove the OW-CPA (i.e., the bare minimum) security of RSA-OAEP. We apply metareductions that show if such reductions existed, then RSA-OAEP would be OW-CCA2 insecure, or even worse, that the RSA problem would solvable. Therefore, it seems unlikely that such reductions could exist. Indeed, no such reductions proving the OW-CCA2 security of RSA-OAEP exist.
Note: Re-written for better clarity in response to various comments.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Published elsewhere. Unknown where it was published
- Keywords
- RSAOAEPProvable SecurityPublic-key EncryptionIND-CCA2OW-CPAImpossibiltiy Results
- Contact author(s)
- dbrown @ certicom com
- History
- 2007-08-08: revised
- 2006-07-03: received
- See all versions
- Short URL
- https://ia.cr/2006/223
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2006/223,
author = {Daniel R. L. Brown},
title = {What Hashes Make RSA-OAEP Secure?},
howpublished = {Cryptology ePrint Archive, Paper 2006/223},
year = {2006},
note = {\url{https://eprint.iacr.org/2006/223}},
url = {https://eprint.iacr.org/2006/223}
}
