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arXiv · 1810.05864

On the security of the hierarchical attribute based encryption scheme proposed by Wang et al

Mohammad Ali·Javad Mohajeri·Mohammad-Reza Sadeghi
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Abstract

Ciphertext-policy hierarchical attribute-based encryption (CP-HABE) is a promising cryptographic primitive for enforcing the fine-grained access control with scalable key delegation and user revocation mechanisms on the outsourced encrypted data in a cloud. Wang et al. (2011) proposed the first CP-HABE scheme and showed that the scheme is semantically secure in the random oracle model [4, 5]. Due to some weakness in its key delegation mechanism, by presenting two attacks, we demonstrate the scheme does not offer any confidentiality and fine-grained access control. In this way, anyone who has just one attribute can recover any outsourced encrypted data in the cloud.

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Mohammad Ali, Javad Mohajeri, Mohammad-Reza Sadeghi. 2018-10-13. On the security of the hierarchical attribute based encryption scheme proposed by Wang et al. https://arxiv.org/abs/1810.05864

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