• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.11 no.6
• /
• pp.303-310
• /
• 2011

Recently, many user authentication schemes using smart cards have been proposed to improve the security weaknesses in user authentication process. In 2009, Wang et al. proposed a more effective and secure dynamic ID-based remote user authentication scheme to improve the security weakness of Das et al.'s scheme, and asserted that the improved scheme is secure against independent of password in authentication phase and provides mutual authentication between the user and the remote server. However, in this paper, we analyze the security of Wang et al. scheme and demonstrate that Wang et al.'s scheme is vulnerable to the man-in-the-middle attack and the off-line password guessing attack. In addition, we show that Wang et al. scheme also fails to provide mutual authentication. Accordingly, we propose an improved scheme to overcome these security weakness even if the secrete information stored in the smart card is revealed. Our proposed scheme can withstand the user impersonation attack, the server masquerading attack and off-line password guessing attack. Furthermore, this improved scheme provides the mutual authentication and is more effective than Wang et al.'s scheme in term of the computational complexities.

• International Journal of Internet, Broadcasting and Communication
• /
• v.8 no.3
• /
• pp.41-49
• /
• 2016

Recently, many biometrics-based user authentication schemes for telecare medicine information systems (TMIS) have been proposed to improve the security problems in user authentication system. In 2014, Mishra et al. proposed an improvement of Awasthi-Srivastava's biometric based authentication for TMIS which is secure against the various attacks and provide mutual authentication, efficient password change. In this paper, we discuss the security of Mishra et al.'s authentication scheme, and we have shown that Mishra et al.'s authentication scheme is still insecure against the various attacks. Also, we proposed the improved scheme to remove these security problems of Mishra et al.'s authentication scheme, even if the secret information stored in the smart card is revealed. As a result, we can see that the improved biometric based authentication scheme is secure against the insider attack, the password guessing attack, the user impersonation attack, the server masquerading attack and provides mutual authentication between the user and the telecare system.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.16 no.2
• /
• pp.121-127
• /
• 2006

Recently, Chang et at.$^[9]$ proposed a new password-based key agreement protocol and a password change protocol to improve the efficiency in the password-based authenticated key agreement protocol proposed by Yeh et at.$^[8]$. However, Wang et al.$^[10]$ showed that their protected password change protocol is not secure under the denial of service attack and the dictionary attack This paper proposes an improved password change protocol to solve this problems in the Chang et al's protocol. In the proposed protocol, the format of communication messages is modified not to have any clue for the guessing of the password and verifying of the guessed password. The proposed protocol supports the advantages in the previous password-based protocols and solves the problems in them effectively.

• International Journal of Internet, Broadcasting and Communication
• /
• v.9 no.3
• /
• pp.35-43
• /
• 2017

In 2013, Lee-Lie proposed secure smart card based authentication scheme of Zhu's authentication for TMIS which is secure against the various attacks and efficient password change. In this paper, we discuss the security of Lee-Lie's smart card-based authentication scheme, and we have shown that Lee-Lie's authentication scheme is still insecure against the various attacks. Also, we proposed the improved scheme to overcome these security problems of Lee-Lie's authentication scheme, even if the secret information stored in the smart card is revealed. As a result, we can see that the improved smart card based user authentication scheme for TMIS is secure against the insider attack, the password guessing attack, the user impersonation attack, the server masquerading attack, the session key generation attack and provides mutual authentication between the user and the telecare system.

• Journal of KIISE:Information Networking
• /
• v.31 no.4
• /
• pp.347-352
• /
• 2004

In this paper, we propose a new key exchange protocol which authenticates each other and shares a session key between a user and a server over an insecure channel using only a small password. The security of the protocol is based on the difficulty of solving the discrete logarithm problem and the Diffie-Hellman problem and the cryptographic strength of hash function. The protocol is secure against the man-in-the-middle attack, the password guessing attack, the Denning-Sacco attack, and the stolen-verifier attack, and provide the perfect forward secrecy. Furthermore, it is more efficient than other well-known protocols in terms of protocol execution time because it could be executed in parallel and has a simple structure.

• Journal of KIISE:Computer Systems and Theory
• /
• v.36 no.4
• /
• pp.304-310
• /
• 2009

Due to widely use of internet, a lot of users frequently access into remote server in distributed computing environment. However, transmitting the information using vulnerable channel without authentication security system can be exposed to replay attack, offline password attack, and impersonation attack. According to this possibility, there is research about authentication protocol to prevent these hostile attacks using smart card. In this paper, we analyze vulnerability of user authentication system based on password and propose modified user authentication system.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.6 no.3
• /
• pp.69-77
• /
• 2010

Authentication and key establishment are fundamental procedures to establish secure communications over public insecure network. A password-based scheme is common method to provide authentication. In 2008, Khan proposed an efficient password-based authentication scheme using smart cards to solve the problems inherent in Wu-Chieu's authentication scheme. As for security, Khan claimed that his scheme is secure and provides mutual authentication between legal users and a remote server. In this paper, we demonstrate Khan's scheme to be vulnerable to various attacks, i. e., password guessing attack, insider attack, reflection attack and forgery attack. Our study shows that Khan's scheme does not provide mutual authentication and is insecure for practical applications. This paper proposes an improved scheme to overcome these problems and to preserve user anonymity that is an issue in e-commerce applications.

• Journal of Internet Computing and Services
• /
• v.10 no.4
• /
• pp.223-230
• /
• 2009

Among the remote user authentication schemes, password-based authentication methods are the most widely used. In 2004, Das et al. proposed a "Dynamic ID Based Remote User Authentication Scheme" that is the password based scheme with smart-cards, and is the light-weight technique using only one-way hash algorithm and XOR calculation. This scheme adopts a dynamic ID that protects against ID-theft attack, and can resist replay attack with timestamp features. Later, many flaws of this scheme were founded that it allows any passwords to be authenticated, and can be vulnerable to impersonation attack, and guessing attack. By this reason many modifications were announced. These scheme including all modifications are similarly maintained security against replay the authentication message attack by the timestamp. But, if advisory can replay the login immediately, this attempt can be succeeded. In this paper, we analyze the security vulnerabilities of Das scheme, and propose improved scheme which can resist on real-time replay attack using the counter of authentication. Besides our scheme still secure against impersonation attack, guessing attack, and also provides mutual authentication feature.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.9
• /
• pp.89-96
• /
• 2021

In this paper, we analyzed that the user authentication scheme for TMIS(Telecare Medicine Information System) proposed by Al-Saggaf et al. In 2019, Al-Saggaf et al. proposed authentication scheme using biometric information, Al-Saggaf et al. claimed that their authentication scheme provides high security against various attacks along with very low computational cost. However in this paper after analyzing Al-Saggaf et al's authentication scheme, the Al-Saggaf et al's one are missing random number s from the DB to calculate the identity of the user from the server, and there is a design error in the authentication scheme due to the lack of delivery method. Al-Saggaf et al also claimed that their authentication scheme were safe against a variety of attacks, but were vulnerable to password guessing attack using login request messages and smart cards, session key exposure and insider attack. An attacker could also use a password to decrypt the stored user's biometric information by encrypting the DB with a password. Exposure of biometric information is a very serious breach of the user's privacy, which could allow an attacker to succeed in the user impersonation. Furthermore, Al-Saggaf et al's authentication schemes are vulnerable to identity guessing attack, which, unlike what they claimed, do not provide significant user anonymity in TMIS.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.2
• /
• pp.159-166
• /
• 2012

Many biometrics-based user authentication schemes using smart cards have been proposed to improve the security weaknesses in user authentication system. In 2010, Chang et al. proposed an improved biometrics-based user authentication scheme without concurrency system which can withstand forgery attack, off-line password guessing attack, replay attack, etc. In this paper, we analyze the security weaknesses of Chang et al.'s scheme and we have shown that Chang et al.'s scheme is still insecure against man-in-the-middle attack, off-line biometrics guessing attack, and does not provide mutual authentication between the user and the server. And we proposed the improved scheme to overcome these security weaknesses, even if the secret information stored in the smart card is revealed. As a result, the proposed scheme is secure for the user authentication attack, the server masquerading attack, the man-in-the-middle attack, and the off-line biometrics guessing attack, does provide the mutual authentication between the user and the remote server. And, in terms of computational complexities, the proposed scheme is more effective than Chang et al.'s scheme.