—Many identity-based public key cryptosystems
from bilinear pairings use hash functions to construct their
public keys. Most of these schemes only specify the need of
applying cryptographic strong or collision free hash functions,
without giving any detail of which or what hash functions should
be used. Traditional understanding of a cryptographic strong
hash function has three security properties, which are pre-image
resistance, second pre-image resistance and collision resistance.
However, with only these three properties, in this paper we show
a potential security vulnerability of identity-based
cryptographic cryptosystems if the hash functions used are not
correctly constructed. To fix this vulnerability, this paper
defines an additional desirable security property for the hash
functions in these identity-based cryptosystems.
—Public key cryptosystems, identity-based
cryptosystems, cryptographic strong hash functions, bilinear
Jyh-Haw Yeh is with the Department of Computer Science, Boise State
University, Boise, ID 83725, USA (e-mail: jhyeh@ boisestate.edu).
Cite:Jyh-Haw Yeh, "Security Vulnerability in Identity-Based Public Key Cryptosystems from Pairings," International Journal of Information and Education Technology vol. 3, no. 4, pp. 466-470, 2013.