Grey-box public-key steganography

Abstract

Steganography is one of the information-hiding techniques. By encoding secret messages to other documents which are meaningful, parties can send the secret messages without any suspicion. Recently, Liśkiewicz, Reischuk, and Wölfel [TAMC 2011] proposed a grey-box model for the channel setting. This model formalizes a more realistic situation that everyone knows partial information of communication. They constructed some schemes of grey-box steganography in the symmetric-key setting. In this paper, we apply their idea of the grey-box model to the public-key setting, and then construct a scheme of grey-box public-key steganography via a standard public-key encryption scheme. We show that our proposed scheme is steganographically secure if the underlying public-key encryption scheme satisfies indistinguishability from random bits. © Springer-Verlag Berlin Heidelberg 2013.