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A protected password change protocol

Ren-Chiun Wang·Chou-Chen Yang·Kun-Ru Mo
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Abstract

Some protected password change protocols were proposed. However, the previous protocols were easily vulnerable to several attacks such as denial of service, password guessing, stolen-verifier and impersonation atacks etc. Recently, Chang et al. proposed a simple authenticated key agreement and protected password change protocol for enhancing the security and efficiency. In this paper, authors shall show that password guessing, denial of service and known-key attacks can work in their password change protocol. At the same time, authors shall propose a new password change protocol to withstand all the threats of security.

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Ren-Chiun Wang, Chou-Chen Yang, Kun-Ru Mo. 2005-06-30. A protected password change protocol. https://arxiv.org/abs/cs/0506105

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