CL-KEM Based Password Authenticated Key Exchange Protocol under DDH Assumption

Password-authenticated key exchange (PAKE) protocols tackle the important problem of how to enable two parties, who share a low-entropy password, to establish a cryptographically strong session key for secure data communication. Although considerable research efforts have been devoted to designing hundreds of PAKE protocols, to the best of our knowledge, there have been few systematic reviews. In this work, we provide a comprehensive overview of PAKE research. We first propose a list of 13 desirable properties of PAKE protocols in terms of security and usability, enabling PAKE protocols to be systematically rated across a common spectrum. We then provide a taxonomy for PAKE protocols, and classify them into seven types according to their underlying design strategies. For each type, we investigate the inner working mechanisms of various representative protocols, and identify their pros, and cons. We further classify existing PAKE protocols from five other key perspectives (i.e., symmetry, number of participants, hardness assumptions, security goals, and round complexity) and review their development history under each classification, aiming to provide an in-depth and thorough understanding of the status quo of PAKE research. Based on 13 properties and six perspectives, we conduct a large-scale comparative evaluation of 71 representative PAKE protocols in a systematic manner. Finally, we highlight a few potential directions for the future design of PAKE protocols.

Password-Authenticated Key Exchange (PAKE) protocols allow parties to share secret keys in an authentic manner based on an easily memorizable password. Recently, Nam et al. showed that a provably secure three-party password-based authenticated key exchange protocol using Weil pairing by Wen et al. is vulnerable to a man-in-the-middle attack. In doing so, Nam et al. showed the flaws in the proof of Wen et al. and described how to fix the problem so that their attack no longer works. In this paper, we show that both Wen et al. and Nam et al. variants fall to key compromise impersonation by any adversary. Our results underline the fact that although the provable security approach is necessary to designing PAKEs, gaps still exist between what can be proven and what are really secure in practice.

A password-authenticated key exchange (PAKE) protocol allows two entities sharing a password to perform mutual authentication and establish a session key. Benefiting from the use of a low-entropy human-memorable password, PAKE avoids the use of PKI in the authentication process, making it more flexible and cheaper. However, with the development of quantum computing, protocols based on classical assumptions will no longer be secure, so designing a PAKE protocol capable of resisting quantum attacks has become an important research direction. In this work, we propose an efficient PAKE protocol using a new error reconciliation mechanism based on the ring learning with errors (RLWE) problem, which is considered to resist quantum attacks. Our protocol is proven security under the Bellare-Pointcheval-Rogaway (BPR) model. The protocol is implemented using the C language, which is highly portable, and is also optimized utilizing the Advanced Vector Extensions 2 (AVX2) instruction set. Compared with the C implementation of Ding’s protocol, our reference C implementation is more than 12x faster, and the efficiency is doubled after AVX2 optimization. Moreover, by choosing the appropriate parameters, the security strength of our scheme is improved and the message size is reduced.

With the popularity of unmanned aerial vehicles (UAVs), more and more valuable data can be collected by UAVs. In order to balance the data usage and communication cost, the data can be preprocessed in UAVs rather than directly transmitting to the data centre in the edge computing paradigm. Users can obtain information of interest by accessing the data centre remotely by authenticating themselves to the data centre using the most pervasive password authentication method. Unfortunately, the data centre becomes the main attack target because it not only stores the data but also maintains the passwords of all the users. Aiming at protecting the data as well as the password in the UAV‐enabled mobile edge computing environment, the authors combine the advantages of gateway‐oriented password authenticated key exchange (PAKE) protocols and two‐server PAKE protocols and put forward an efficient gateway‐oriented two‐server PAKE protocol. The security of the proposed protocol is given in the random oracle model. The performance comparison shows their proposal has comparable efficiency in computation and communication costs. Their protocol provides better protection to the password without sacrificing efficiency. Consequently, their protocol is more suitable for real applications in UAV‐enabled mobile edge computing environment.

In recent years, many password authenticated key exchange (PAKE) protocols have been proposed. However, many of them have been broken or have no security proof. In this paper, we propose an efficient password authenticated key exchange protocol using bilinear pairings. Compared with previous PAKE protocol using bilinear pairings, our protocol is quite efficient both in communication cost and computational cost. Moreover, this paper proves that the novel protocol is forward secrecy under the Bilinear Diffie-Hellman (BDH) assumption in the random oracle model.KeywordsPAKEbilinear paringBDHforward secrecy

We analyze the Secure Remote Password (SRP) protocol for structural weaknesses using the Cryptographic Protocol Shapes Analyzer (CPSA) in the first formal analysis of SRP (specifically, Version 3).SRP is a widely deployed Password Authenticated Key Exchange (PAKE) protocol used in 1Password, iCloud Keychain, and other products. As with many PAKE protocols, two participants use knowledge of a pre-shared password to authenticate each other and establish a session key. SRP aims to resist dictionary attacks, not store plaintext-equivalent passwords on the server, avoid patent infringement, and avoid export controls by not using encryption. Formal analysis of SRP is challenging in part because existing tools provide no simple way to reason about its use of the mathematical expression \(v + g^b \mod q\).Modeling \(v + g^b\) as encryption, we complete an exhaustive study of all possible execution sequences of SRP. Ignoring possible algebraic attacks, this analysis detects no major structural weakness, and in particular no leakage of any secrets. We do uncover one notable weakness of SRP, which follows from its design constraints. It is possible for a malicious server to fake an authentication session with a client, without the client’s participation. This action might facilitate an escalation of privilege attack, if the client has higher privileges than does the server. We conceived of this attack before we used CPSA and confirmed it by generating corresponding execution shapes using CPSA.KeywordsCryptographic protocolsCryptographyCryptographic Protocol Shapes Analyzer (CPSA)CybersecurityFormal methodsPassword Authenticated Key Exchange (PAKE) protocolsProtocol analysisSecure Remote Protocol (SRP)UMBC Protocol Analysis Lab (PAL)

We revisit the problem of protecting user's private data against adversarial compromise of user's device(s) which store this data. We formalize the solution we propose as Password-Protected Secret-Sharing (PPSS), which allows a user to secret-share her data among n trustees in such a way that (1) the user can retrieve the shared secret upon entering a correct password into a reconstruction protocol, which succeeds as long as at least t+1 uncorrupted trustees are accessible, and (2) the shared data remains secret even if the adversary which corrupts t trustees, with the level of protection expected of password-authentication, i.e. the probability that the adversary learns anything useful about the secret is at most q/|D| where q is the number of reconstruction protocol the adversary manages to trigger and |D| is the size of the password dictionary. We propose an efficient PPSS protocol in the PKI model, secure under the DDH assumption, using non-interactive zero-knowledge proofs with efficient instantiations in the Random Oracle Model. Our protocol is practical, with fewer than 16 exponentiations per trustee and 8t+17 exponentiations per user, with O(1) bandwidth between the user and each trustee, and only three message flows, implying a single round of interaction in the on-line phase. As a side benefit our PPSS protocol yields a new Threshold Password Authenticated Key Exchange (T-PAKE) protocol in the PKI model with significantly lower message, communication, and server computation complexities then existing T-PAKE's.

An improved password-authenticated key exchange protocol for VANET

Authentication has been a cornerstone of computer security for decades. A considerable number of authentication protocols have been specified and implemented. This paper compares most common families of client-server authentication protocols and shows the benefits of the combined use of One Time Password (OTP) with Password Authenticated Key Exchange (PAKE) protocols. Then, the paper addresses a particular issue inherited from this combination which consists in the synchronization between the client and the server. We propose an optimized implementation for a synchronization mechanism based on the use of a synchronization window. The optimized synchronization has been implemented and the simulation results show that our proposal significantly reduces the computations needed at the client side to select the current password.

We study three-party, password-authenticated key exchange protocols where the trusted third party has a high-entropy private key to which corresponds a public key. In this scenario we can maintain the user-friendliness of password authentication while provably achieving security properties that ordinary password-authenticated key exchange protocols cannot, namely resistance against key compromise impersonation and a special form of internal state revealing. We define security models tailored to our case and illustrate our work with several protocols.

There have been many proposals in recent years for password-authenticated key exchange protocols.Man y of these have been shown to be insecure, and the only ones that seemed likely to be proven secure (against active adversaries who may attempt to perform off-line dictionary attacks against the password) were based on the Diffie-Hellman problem. In fact, some protocols based on Diffie-Hellman have been recently proven secure in the random-oracle model. We examine how to design a provably-secure password-authenticated key exchange protocol based on RSA.We first look at the OKE and protected-OKE protocols (both RSA-based) and show that they are insecure.Then we show how to modify the OKE protocol to obtain a password-authenticated key exchange protocol that can be proven secure (in the random oracle model). The resulting protocol is very practical; in fact the basic protocol requires about the same amount of computation as the Diffie-Hellman-based protocols or the well-known ssh protocol.

In this paper, security of ID documents (such as passports) is discussed. A class of cryptographic protocols called Password-Authenticated Key Exchange (PAKE) provides a more robust solution to this problem. PAKE protocols ensure that an eavesdropper can't learn any information on the low-entropy secret. They're also required to be as secure as possible against all passive and active attacks. Basically, all an adversary can do to learn the password is an online dictionary attack (guess the password and try to execute the protocol with one of the parties). We can prevent this through latency, smart card blocking, and so on. For implementing PAKE protocols, especially in constrained environments such as e-passports, elliptic-curve cryptography is fast and requires little memory. However, it involves representing numeric values (in this case, passwords) as points on an elliptic curve, and how to do this efficiently and se curely isn't obvious.

Simultaneous Authentication of Equals (SAE) is a password-authenticated key exchange protocol that is designed to replace the WPA2-PSK-based authentication. The SAE authenticated key exchange protocol supports the peer-to-peer authentication and is one of the major authentication mechanisms of the Authentication and Key Management Suite specified within Wi-Fi. The SAE authenticated key exchange protocol has been widely implemented in today’s Wi-Fi devices as part of major security feature upgrades and is regarded as the third generation of Wi-Fi Protected Access. This article presents a way of attacking the weaker randomness generation algorithm within the SAE protocols, which can lead to successful impersonation types of attacks. We also suggest some protocol amendments for protection. It is recommended that SAE implementations should be upgraded to ensure protection against these attacks.

Although two-party password-authenticated key exchange protocols have been intensively studied in recent years, group password-authenticated key exchange protocols have received little attention. In this paper, we propose a group password-authenticated key exchange protocol with key confirmation for the independent-password setting, where each party shares an independent password with a trusted server. This proposed protocol is based on 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sup> -cube group key exchange protocol. In this paper, we also present a formal statement of its security in a variant of the Bresson et al. security model.

Boyko et al. presented two protocols called PAK and PAK-X which are the password-authenticated key exchange protocol based on the Diffie-Hellman algorithm to provide a formal proof of security in the random oracle model. These protocols have very good property and were submitted to IEEE P1363.2 for public key cryptography: password-based techniques. However, they are not the most efficient methods in the perspective of the total execution time because they do not provide parallelizability to each party. Therefore, the purpose of this paper is to speed up these schemes by supporting parallel computability to both parties. This paper proposes two protocols, PPAK and PPAK-X, which are parallelizable password-authenticated key exchange protocols while maintaining provable security in PAK and PAK-X by simply modifying their structures.