Research on key leakage-verifiable searchable encryption with post-compromise security
Wei Wang, Shubin Lei, Dongli Liu, Peng Xu, Laurence Tianruo Yang · Scientia Sinica Informationis · 2025
Searchable encryption technology can enable secure search over encrypted data, ensuring the security of searching for users on a cloud server. However, the risk of key leakage in practical applications poses a significant threat to the security and privacy of data. The previous work Bamboo enables key update after key leakage and ensures the security of ciphertexts between key leakage and key update through two-layer encryption and hidden chain structure, but it does not consider how to detect key leakage to trigger key update actively. Therefore, this paper proposes a key leakage-verifiable dynamic searchable symmetric encryption (DSSE) scheme called KLVSE based on key-updatable technology. It introduces a bidirectional verification mechanism to verify key leakage events and detect potential illegal search behavior by the adversary. This ensures that key updates are triggered immediately after key leakage and guarantees post-compromise security. The experimental results demonstrate that compared to the traditional periodic key update strategy, this scheme achieves key leakage verification with a sufficiently small runtime delay while ensuring security, effectively safeguarding the security and privacy of user data.