Cryptanalysis and Improvement of Efficient Password-Based User Authentication Scheme using Hash Function

Remote user authentication is a mechanism in which the remote server verifies the legitimacy of a user over an insecure communication channel. Password based authentication schemes have been widely deployed to verify the legitimacy of remote users as password authentication is one of the simplest and the most convenient authentication mechanism over insecure networks. In remote user authentication scheme, the user is assigned a smart card, which is being personalized by some parameters and provide the legal users to use the resources of the remote system. Until now, there have been ample of remote user authentication schemes published in the literature and each published schemes have its own merits and demerits. Recently, many schemes proposed are based on the one-way hash function. The computational complexity of their schemes is superior to the discrete logarithm-problem-based schemes. In our paper, we have defined all the security requirements and the goals. An ideal password authentication schemes should satisfy and achieve all of these. We have presented the results of our survey through five of the currently available secure one way hash function based remote user authentication schemes. We hope an ideal smart card (not storing (ID i ,PW i ), which meets all the security requirements and achieves all the goals can be developed.

Remote mutual authentication is an important part of security, along with confidentiality and integrity, for systems that allow remote access over untrustworthy networks, like the Internet. In 2006, Shieh-Wang pointed out the weakness of Juang's remote mutual authentication scheme using smart card and further proposed a novel remote user authentication scheme using smart card. However, this paper demonstrates that Shieh-Wang's scheme still does not provide perfect forward secrecy and is vulnerable to a privileged insider's attack. We also present an improved scheme based on the Elliptic Curve Diffie-Hellman problem (ECDHP) and secure one-way hash function, in order to isolate such security problems.

사용자 인증 스킴은 개방된 통신환경에서 원격지에 있는 사용자가 서버에 로긴할 때 정당한 사용자 인지를 확인하는 것이다. 2005년 Liao등은 스마트 카드를 이용해서 사용자의 익명성을 보장하는 사용자 인증 스킴을 제안하였다. 최근 Yoon등은 Liao가 제안한 사용자 인증 스킴의 안전성 분석을 수행한 후 그 스킴에 존재하는 결점을 보완하는 향상된 스킴을 제안하였다. 그러나 안타깝게도 그들이 제안한 스킴은 사용자가 서버를 인증하는 방식과 서버가 사용자를 인증 방식을 모두 수행할 수 없고 패스워드의 안전성에도 문제점이 존재한다. 이러한 문제점을 이 논문에서는 서버 가장 공격, 사용자 가장 공격, 오프라인 사전공격을 수행하여 지적하였다. 아울러 본 논문에서는 Yoon등이 제안한 논문의 취약점을 제거하여 보다 안전한 사용자 인증 스킴을 제안하였다. A remote user authentication scheme is a two-party protocol whereby an authentication server in a distributed system confirms the identity of a remote individual logging on to the server over an untrusted, open network. In 2005, Liao et al. proposed a remote user authentication scheme using a smart card, in which users can be authenticated anonymously. Recently, Yoon et al. have discovered some security flaws in Liao et al.'s authentication scheme and proposed an improved version of this scheme to fix the security flaws. In this article, we review the improved authentication scheme by Yoon et al. and provide a security analysis on the scheme. Our analysis shows that Yoon et al.'s scheme does not guarantee not only any kind of authentication, either server-to-user authentication or user-to-server authentication but also password security. The contribution of the current work is to demonstrate these by mounting two attacks, a server impersonation attack and a user impersonation attack, and an off-line dictionary attack on Yoon et al.'s scheme. In addition, we propose the enhanced authentication scheme that eliminates the security vulnerabilities of Yoon et al.'s scheme.

In 1999, Hwang and Li proposed a new user authentication scheme using smart cards. The scheme does not need any password or verification table. Later, Sun proposed an efficient remote use authentication scheme to improve the efficiency of the Hwang-Li scheme. However, these two schemes do not allow users to freely choose and change their passwords. In this article, we shall propose a simple and efficient remote user authentication scheme that allows users to freely choose and change their passwords without significantly increasing the computation cost.

There are many remote user authentication schemes proposed in literatures for preventing unauthorized parties from accessing resources in an insecure environment. Due to inherent tamper-resistance, most of them are based on smart card authentication schemes. Unfortunately, the cost of cards and readers make these schemes costly. In the real world, common storage devices, such as universal serial bus (USB) thumb drives, portable HDDs, mobile phones, Laptop or Desktop PCs, are widely used, and they are much cheaper or more convenient for storing user authentication information. However, since these devices do not provide tamper-resistance, it is a challenge to design a secure authentication scheme using these kinds of memory devices. In this paper, we will propose a secure password-based remote user authentication and key agreement scheme without using smart cards. According to our analysis, the proposed scheme guarantees mutual authentication and also resists off-line dictionary, replay, forgery, and impersonation attacks. Compared to related scheme, the proposed scheme’s computation cost is lower and the total message length is shorter. Therefore, our scheme is suitable even for applications in limited power computing environments.DOI: http://dx.doi.org/10.5755/j01.itc.41.1.975

In 2005, Lee et al. proposed a secure smart card based remote user authentication scheme to improve the security of Chien et al.'s scheme. More recently, Sood et al. pointed out that Lee et al.'s scheme is still vulnerable to the reflection attack, off-line password guessing attack, user impersonation attack and fails to preserve user anonymity. Consequently, Sood et al. proposed a more secure remote user authentication scheme, which is an improvement over Lee et al.'s scheme to overcome their security drawbacks. In this study, however, we find that Sood et al.'s scheme still cannot achieve the claimed security and report its following flaws: (1) It fails to preserve user anonymity under their non-tamper resistance assumption of the smart card; (2) It cannot withstand stolen-verifier attack. The proposed cryptanalysis discourages any use of the scheme for practical applications.

Authentication is one of the fundamental mechanisms to enable a legitimate user to log into a remote server in an insecure environment. Many authentication protocols have been proposed in the literature for preventing unauthorized parties from access resources. Recently, Chen et al. proposed a password-based remote user authentication and key agreement scheme using common storage devices, such as USB sticks. They claimed that the scheme can withstand off-line dictionary attacks even if the authentication information stored in the device is obtained by the adversary. However, we observe that Chen et al.’s scheme is insecure against off-line dictionary attacks in this case. To remedy this security flaw, we propose an improved authentication protocol without using smart cards. Compared with the previous schemes, our scheme not only provides more security guarantees, but also is more efficient both in computation and communication cost.DOI: http://dx.doi.org/10.5755/j01.itc.42.2.2079

In a remote user authentication scheme, a remote server verifies whether a login user is genuine and trustworthy. Several remote user authentication schemes using the password, the biometrics and the smart card have been proposed in the literature. In 2012, Sonwanshi et al. proposed a password-based remote user authentication scheme using smart card, which uses the hash function and bitwise XOR operation. Their scheme is very efficient because of the usage of efficient one-way hash function and bitwise XOR operations. They claimed that their scheme is secure against several known attacks. Unfortunately, in this paper we find that their scheme has several vulnerabilities including the offline password guessing attack and stolen smart card attack. In addition, we show that their scheme fails to protect strong replay attack.

Recently, remote user authentication schemes using smart cards has been researched to provide user privacy because of increasing interest and demands. Previously, provided authentication schemes were only concerned about providing user privacy against outside attackers, but the scheme, which guarantees user privacy against both a remote server and outside attackers, has been recently demanded because the user's information has leaked out through the service providers. When the remote server perceives a user doing a malicious act, the server should be able to trace the malicious user by receiving help from a trust agency. In this paper, we suggest a scheme which not only guarantees user privacy against both a remote server and outside attackers, but also provides traceable anonymity authentication.

Recently, because the interest and needs in privacy protection are growing, smartcard-based remote user authentication schemes have been actively studied to provide the user anonymity. In 2008, Kim et al. first proposed an authentication scheme in order to ensure the user anonymity against both external attackers and the remote server and track malicious users with the help of a trusted trace sever. However, in 2010, Lee et al. showed that Kim et al.`s scheme cannot provide the user anonymity against remote server, which is because the server can trace users without any help of the trace server, and then proposed a improved scheme. On the other hand, in 2010, Horng et al. proposed an authentication scheme with non-tamper resistant smart cards, in which the non-tamper resistant smart card means that an attacker may find out secret information stored in the smart card through special data analysis techniques such as monitoring power consumption, to be secure against a variety of attacks and to provide the user anonymity against external attackers. In this paper, we will propose a remote user authentication scheme with non-tamper resistant smart cards not only to ensure the user anonymity against both external attackers and the remote server but also to track malicious users with only the help of a trusted trace sever.

In 2005, Yoon et al. proposed a user-friendly remote user authentication scheme using smart cards. The security of their scheme is based on one-way hash function and they claimed that their scheme is secured from attacks and achievable for proving mutual authentication, freely choosing password, no verification tables, and involving very lightweight hashing operations. However, we find that Yoon et al.'s scheme suffers from the denial of service attack and performs only unilateral authentication (only user authentication). In this paper we consequently propose an enhanced version to eliminate the vulnerability. Furthermore, our enhanced scheme can also provide mutual authentication and key agreement between a remote server and login users.

A remote user authentication scheme is a two-party protocol whereby an authentication server in a distributed system confirms the identity of a remote individual logging on to the server over an untrusted, open network. Recently, Lee et al. have proposed an efficient nonce-based scheme for remote user authentication using smart cards. This work reviews Lee et al.'s authentication scheme and provides a security analysis on the scheme. Our analysis shows that Lee et al.'s scheme does not achieve its basic aim of authenticating remote users and furthermore has a very hazardous method for changing passwords. In addition, we recommend some changes to the scheme so that it can attain at least its main security goal.

In 2002, Lee, Hwang, and Yang proposed a verifier-free remote user authentication scheme using smart cards. Their scheme is efficient because of mainly using cryptographic hash functions. However, we find that Lee-Hwang-Yang's scheme is not reparable once the user's permanent secret is compromised and is vulnerable to a privileged insider's attack. Furthermore, it lacks the user eviction mechanism. In this paper, we first show the weaknesses of Lee-Hwang-Yang's scheme, and then compare Lee-Hwang-Yang's scheme with three similar schemes.

Password as an easy-to-remember credential plays an important role in remote user authentication schemes, while drawing from a space so small that an adversary may exhaustively search all possible candidate passwords to guess the correct one. In order to enhance the security of the password authentication scheme, smart card is introduced as the second factor to construct two-factor authentication scheme. However, we find out that two latest smart-card-based password authentication schemes are vulnerable to offline password guessing attacks under the definition of secure two-factor authentication. Furthermore, in order to show the serious consequence of offline password guessing attacks, we illustrate that the password compromise impersonation attacks as further threats are effective to break down the authentication schemes. Finally, we conclude the reasons why these weaknesses exist and present our improved ideas to avoid these problems in the future.

Benefited from the development of network and communication technologies, E-health care systems and telemedicine have got the fast development. By using the E-health care systems, patient can enjoy the remote medical service provided by the medical server. Medical data are important privacy information for patient, so it is an important issue to ensure the secure of transmitted medical data through public network. Authentication scheme can thwart unauthorized users from accessing services via insecure network environments, so user authentication with privacy protection is an important mechanism for the security of E-health care systems. Recently, based on three factors (password, biometric and smart card), an user authentication scheme for E-health care systems was been proposed by Amin et al., and they claimed that their scheme can withstand most of common attacks. Unfortunate, we find that their scheme cannot achieve the untraceability feature of the patient. Besides, their scheme lacks a password check mechanism such that it is inefficient to find the unauthorized login by the mistake of input a wrong password. Due to the same reason, their scheme is vulnerable to Denial of Service (DoS) attack if the patient updates the password mistakenly by using a wrong password. In order improve the security level of authentication scheme for E-health care application, a robust user authentication scheme with privacy protection is proposed for E-health care systems. Then, security prove of our scheme are analysed. Security and performance analyses show that our scheme is more powerful and secure for E-health care systems when compared with other related schemes.