RSA Over-Encryption Employing RGB Channels through a Steganography Variant

Abstract

This study aims to provide a solution for RSA over-encryption based on steganography variant to hide sensitive information that requires security. The current study describes a software program's implementation phases that allow technicians to re-encrypt a message, first encoded using RSA cryptosystems as an extra security layer. Subsequently, this text was converted into an array of bytes stored in Red, Green, and Blue (RGB) layers of one or more generated images, which will finally be sent to the receiver. The programming recursion technique was used to determine the number of images that need to be sent and the bytes corresponding to each of them. These images were created, reorganized, and encrypted according to pre-defined rules. The security of the proposed method relies heavily on the probability theory. Each of the possible patterns that can store data is equally likely to be chosen by an attacker. The program also uses as a conceptual base the Least Significant Bit Substitution (LSB) technique, with the difference that it directly stores bytes for the RGB values of the generated image(s). Our results indicate that the re-encryption is independent of a carrier image. The number of different ways to organize the pixels and the generated images suggests an acceptable security level. Moreover, it requires a not negligible computational power to decipher the pixels' original order and the channels containing relevant information.