Traceable and revocable large universe multi-authority attribute-based access control with resisting key abuse

Attribute-based encryption (ABE) is a novel cryptographic technology that enables fine-grained access control over encrypted data. However, there are some problems in the existing attribute-based access control schemes such as key abuse and the requirements of large-scale cross-domain dynamic cooperation. To solve these problems, the author proposes a traceable and revocable large-universe multi-authority attribute-based access control scheme with resisting key abuse (TRKA-D-ABE) with static security under the q-DPBDHE2 assumption. TRKA-D-ABE realizes the dynamic change of attributes, users, and authorities to suit large-scale cross-domain dynamic collaboration by supporting user-attribute revocation, large universes of attributes, users, and authorities. The revocation mechanism resists collusion attacks from both revoked and unrevoked users. It also fulfills the criteria for both forward and backward security. TRKA-D-ABE also implements robust security measures to prevent key abuse attacks from the CSP, authorities, and users. Neither the CSP nor the authority can create a complete decryption key. They are also unable to access any encrypted data, even if their controlled attributes meet the access structure. Users who expose the key will be identified through traceability and punished by revocation. Additionally, users can outsource decryption without key transfer to conserve resources. Based on performance analysis results, TRKA-D-ABE is highly efficient.