Multi-Authority Ciphertext-Policy Attribute Based Encryption With Accountability

TL;DR

This paper introduces a multi-authority ciphertext-policy attribute-based encryption scheme that enhances security and accountability by preventing collusion, hiding access policies, and tracing malicious users, while ensuring security under IND-CPA.

Contribution

It proposes a novel multi-authority ABE scheme with hidden access policies, user accountability, and resistance to authority collusion, addressing security and traceability issues.

Findings

Scheme is secure under selective-set IND-CPA

Can trace malicious users through user ID extraction

Prevents authorities from colluding to decrypt ciphertext

Abstract

Attribute-based encryption (ABE) is a promising tool for implementing fine-grained access control.To solve the matters of security in single authority, access policy public, not traceable of malicious user,we proposed a scheme of multi-authority. Moreover, multi-authority may bring about the collusion of different authorities.In order to solve these problem,we proposed a scheme of access tree structure with policy hidden and access complex.Once the private key is leaked, our scheme can extract the user ID and find it.If the authorities share their information with each other,the scheme avoid them to combine together to compute the key information and decrypt the ciphertext.Finally,the scheme proved to be secure under selective-set of IND-CPA.