Sufficient condition for ephemeral key-leakage resilient tripartite key exchange

17th Australasian Conference on Information Security and Privacy, ACISP 2012; Wollongong, NSW; Australia; 9 July 2012 through 11 July 2012Tripartite (Diffie-Hellman) Key Exchange (3KE), introduced by Joux (ANTS-IV 2000), represents today the only known class of group key exchange protocols, in which computation of unauthenticated session keys requires one round and proceeds with minimal computation and communication overhead. The first one-round authenticated 3KE version that preserved the unique efficiency properties of the original protocol and strengthened its security towards resilience against leakage of ephemeral (session-dependent) secrets was proposed recently by Manulis, Suzuki, and Ustaoglu (ICISC 2009). In this work we explore sufficient conditions for building such protocols. We define a set of admissible polynomials and show how their construction generically implies 3KE protocols with the desired security and efficiency properties. Our result generalizes the previous 3KE protocol and gives rise to many new authenticated constructions, all of which enjoy forward secrecy and resilience to ephemeral key-leakage under the gap Bilinear Diffie-Hellman assumption in the random oracle model. © 2012 Springer-Verlag

An Enhanced One-round Pairing-based Tripartite Authenticated Key Agreement Protocol

A tripartite authenticated key agreement protocol is generally designed to accommodate the need of three specific entities in communicating over an open network with a shared secret key, which is used to preserve data confidentiality and integrity. Since Joux proposed the first pairing-based one-round tripartite key agreement protocol in 2000, numerous authenticated protocols have been proposed after then. However, most of them have turned out to be flawed due to their inability in achieving some desirable security attributes. In 2005, Lin-Li had identified the weaknesses of Shim\u27s protocol and subsequently proposed their improved scheme by introducing an extra verification process. In this paper, we prove that Lin-Li\u27s improved scheme remains insecure due to its susceptibility to the insider impersonation attack. Based on this, we propose an enhanced scheme which will not only conquer their defects, but also preserves the desired security attributes of a key agreement protocol

Security Analysis of Shim\u27s Authenticated Key Agreement Protocols from Pairings

Recently, Shim proposed a tripartite authenticated key agreement protocol from Weil pairing to overcome the security flaw in Joux\u27s protocol. Later, Shim also proposed an ID-based authenticated key agreement protocol which is an improvement of Smart\u27s protocol in order to provide the forward secrecy. In this paper, we show that these two protocols are insecure against the key-compromise impersonation attack and the man-in-the-middle attack respectively

Comments: Insider attack on Cheng et al.\u27s pairing-based tripartite key agreement protocols

Recently, Cheng et al. proposed two tripartite key agreement protocols from pairings: one is certificate-based and the other is identity-based (ID-based). In this article, we show that the two schemes are vulnerable to the insider impersonation attack and the ID-based scheme even discloses the entities¡¦ private keys. Solutions to this problem are discussed

Weakness of Several Identity-based Tripartite Authenticated Key Agreement Protocols

Key agreement allows multi-parties exchanging public information to create a common secret key that is known only to those entities over an insecure network. In recent years, several identity-based authenticated key agreement protocols have been proposed. In this study, we analyze three identity-based tripartite authenticated key agreement protocols. After the analysis, we found that these protocols do not possess the desirable security attributes

Two secure non-symmetric role Key-Agreement protocols

Recently, some two-party Authenticated Key Agreement protocols over elliptic curve based algebraic groups, in the context of Identity-Based cryptography have been proposed. The main contribution of this category of protocols is to reduce the complexity of performing algebraic operations through eliminating the need to using Bilinear Pairings. In this paper, we proposed two novel Identity-Based Authenticated Key Agreement protocols over non-symmetric role participants without using Bilinear Pairings. The results show that our proposed schemes beside of supporting security requirements of Key Agreement protocols, require a subset of operations with low complexity in compare with related protocols in this scientific area

Cryptographic Schemes based on Elliptic Curve Pairings

This thesis introduces the concept of certificateless public key cryptography (CLPKC). Elliptic curve pairings are then used to make concrete CL-PKC schemes and are also used to make other efficient key agreement protocols. CL-PKC can be viewed as a model for the use of public key cryptography that is intermediate between traditional certificated PKC and ID-PKC. This is because, in contrast to traditional public key cryptographic systems, CL-PKC does not require the use of certificates to guarantee the authenticity of public keys. It does rely on the use of a trusted authority (TA) who is in possession of a master key. In this respect, CL-PKC is similar to identity-based public key cryptography (ID-PKC). On the other hand, CL-PKC does not suffer from the key escrow property that is inherent in ID-PKC. Applications for the new infrastructure are discussed. We exemplify how CL-PKC schemes can be constructed by constructing several certificateless public key encryption schemes and modifying other existing ID based schemes. The lack of certificates and the desire to prove the schemes secure in the presence of an adversary who has access to the master key or has the ability to replace public keys, requires the careful development of new security models. We prove that some of our schemes are secure, provided that the Bilinear Diffie-Hellman Problem is hard. We then examine Joux’s protocol, which is a one round, tripartite key agreement protocol that is more bandwidth-efficient than any previous three-party key agreement protocol, however, Joux’s protocol is insecure, suffering from a simple man-in-the-middle attack. We show how to make Joux’s protocol secure, presenting several tripartite, authenticated key agreement protocols that still require only one round of communication. The security properties of the new protocols are studied. Applications for the protocols are also discussed

An Improved ID-based Authenticated Group Key Agreement Scheme

Authenticated group key agreement problem is important in many modern collaborative and distributed applications. There are two ID-based authenticated group key agreement schemes have been proposed by Choi et al. and us, which are based on bilinear pairings and BD scheme. Recently, Zhang and Chen propose an impersonation attack on the two schemes, which means the schemes are not fully authenticated. In this paper, we propose an improved ID-based authenticated group key agreement scheme which can resist this attack

A JSON Token-Based Authentication and Access Management Schema for Cloud SaaS Applications

Cloud computing is significantly reshaping the computing industry built around core concepts such as virtualization, processing power, connectivity and elasticity to store and share IT resources via a broad network. It has emerged as the key technology that unleashes the potency of Big Data, Internet of Things, Mobile and Web Applications, and other related technologies, but it also comes with its challenges - such as governance, security, and privacy. This paper is focused on the security and privacy challenges of cloud computing with specific reference to user authentication and access management for cloud SaaS applications. The suggested model uses a framework that harnesses the stateless and secure nature of JWT for client authentication and session management. Furthermore, authorized access to protected cloud SaaS resources have been efficiently managed. Accordingly, a Policy Match Gate (PMG) component and a Policy Activity Monitor (PAM) component have been introduced. In addition, other subcomponents such as a Policy Validation Unit (PVU) and a Policy Proxy DB (PPDB) have also been established for optimized service delivery. A theoretical analysis of the proposed model portrays a system that is secure, lightweight and highly scalable for improved cloud resource security and management.Comment: 6 Page

Cryptanalysis of Two ID-based Authenticated Key Agreement Protocols from Pairings

Recently, a number of ID-based two-party authenticated key agreement protocols which make of bilinear pairings have been proposed \cite {CJL,MB,Sh,S,X}. In this paper, we show that the Xie\u27s protocol \cite {X} does not provide implicit key authentication and key-compromise impersonation resilience. Also, we point out the vulnerability of the Choi {\it et al}\u27s protocol \cite {CJL} against signature forgery attacks