Showing papers on "Plaintext-aware encryption published in 2019"
TL;DR: An implementation of digital image encryption scheme based on the Lorenz chaotic system is proposed and the hash value of the plain image is embedded in the proposed cryptosystem to dynamically alter the initial secret keys to increase the security level.
Abstract: Over the past two decades, chaos-based encryption appeared as an original application for nonlinear dynamics and deterministic chaos to encrypt and decrypt data. In this paper, an implementation of digital image encryption scheme based on the Lorenz chaotic system is proposed. While in the process of generating chaotic key stream, the hash value of the plain image is embedded in the proposed cryptosystem to dynamically alter the initial secret keys to increase the security level. The proposed digital image encryption algorithm is described in detail along with its security analysis and implementation. The experimental results show that the proposed digital image encryption algorithm is efficient and has high security features and is suitable for practical uses across insecure networks.
47 citations
TL;DR: This paper proposes Bastion, a novel and efficient scheme that guarantees data confidentiality even if the encryption key is leaked and the adversary has access to almost all ciphertext blocks, and evaluates its performance by means of a prototype implementation.
Abstract: Recent news reveal a powerful attacker which breaks data confidentiality by acquiring cryptographic keys, by means of coercion or backdoors in cryptographic software. Once the encryption key is exposed, the only viable measure to preserve data confidentiality is to limit the attacker's access to the ciphertext. This may be achieved, for example, by spreading ciphertext blocks across servers in multiple administrative domains—thus assuming that the adversary cannot compromise all of them. Nevertheless, if data is encrypted with existing schemes, an adversary equipped with the encryption key, can still compromise a single server and decrypt the ciphertext blocks stored therein. In this paper, we study data confidentiality against an adversary which knows the encryption key and has access to a large fraction of the ciphertext blocks. To this end, we propose $\mathrm{Bastion}$ Bastion , a novel and efficient scheme that guarantees data confidentiality even if the encryption key is leaked and the adversary has access to almost all ciphertext blocks. We analyze the security of $\mathrm{Bastion}$ Bastion , and we evaluate its performance by means of a prototype implementation. We also discuss practical insights with respect to the integration of $\mathrm{Bastion}$ Bastion in commercial dispersed storage systems. Our evaluation results suggest that $\mathrm{Bastion}$ Bastion is well-suited for integration in existing systems since it incurs less than 5 percent overhead compared to existing semantically secure encryption modes.
27 citations
TL;DR: It is demonstrated that the security of their proposed variant of ElGamal encryption scheme is not secure as claimed and whether an additively homomorphic cryptosytem satisfying the desired properties exists remains an open question.
Abstract: Recently, based on the Paillier cryptosystem [1] , Yi et al outline a distributed ElGamal cryptosystem which allows for both a much simpler distributed key generation procedure and a more efficient distributed decryption of messages from a large plaintext domain [2] In this paper, we analyze the security of their proposed variant of ElGamal encryption scheme and demonstrate that their proposed variant is not secure as claimed Thus, whether an additively homomorphic cryptosytem satisfying the desired properties exists remains an open question
13 citations
TL;DR: A stream cipher called Modified Rivest Cipher 4 that overcome several weaknesses of the RC4 is proposed that could provide security as well as allow us to watermarking these compressed encrypted data.
Abstract: As there is rapid revolution in digital multimedia which is in compressed encrypted format, the ability for creating similar and unauthorized data, that can be easily copied, manipulated and distributed has been increased. Hence for copyright management protection, ownership identification, tamper detection and for other security issues watermarking has to be carried out for tamper proofing, quality assessment and copy control for those media content. Thus there is a need for an encryption scheme which could provide security as well as allow us to watermarking these compressed encrypted data. For encryption we propose a stream cipher called Modified Rivest Cipher 4 that overcome several weaknesses of the RC4. The embedding capacity, robustness, perceptual quality and security of the proposed algorithm, using the watermarking schemes: spread spectrum, scalar costa scheme quantization index modulation has been proposed and the comparison based on PSNR, MSE and BER values has been done between various encryption algorithms.
2 citations