Key-based steganographic textual secret sharing for confidential messaging

Abstract

Many email communications remain unencrypted between end points, raising the need for additional encryption. This paper addresses the need by proposing a new cryptographic scheme, which first encrypts a message using key-based Shamir’s secret sharing (using multiple polynomial terms as opposed to only the constant) and discretely hides the shares throughout a cover image using a steganographic technique with number padding. It thus employs multi-layer security requiring the key, the original cover image and the decryption algorithm implementation to unlock the message. Its security is analysed, confirmed and an example given.