Password based authentication with smart cards has been adopted as a more secure means in insecure networks to validate the legitimacy of users. Traditional authentication schemes are based on the tamper-resistant smart card; that is, the data stored in the smart card cannot be revealed. However, it is a challenging problem for considering non-tamper-resistant smart cards used in user authentication. Very recently, in 2010, Song proposed an efficient authentication scheme with such non-tamper resistant smart cards based on symmetric key cryptosystems as well as modular exponentiations. In this paper, we will show that Song's scheme is vulnerable to the offline password guessing attack and the insider attack. Besides, this scheme does not provide perfect forward secrecy and does not preserve user anonymity.
2010 International Conference on Progress in Informatics and Computing Conference (PIC-2010), Shanghai, China, pp.477-480