An Enhanced-Security Certificateless Aggregate Signcryption for Secure Data Transmission in Resource-Constrained Networks

The terminal devices in resource-constrained networks face significant challenges in ensuring data privacy and integrity during transmission. Signcryption, which simultaneously provides both data confidentiality and authentication, offers a promising solution with reduced computational costs in such networks. Recently, three efficient pairing-avoiding certificateless aggregate signcryption (CLASC) schemes were introduced to enhance privacy and authenticity in vehicular sensor networks, the Industrial Internet of Thing, and 5G wireless network scenarios. These schemes achieve lower computational costs compared to previous schemes. However, further security analysis reveals that these CLASC schemes fail to meet their claimed security properties. Specifically, two of them are vulnerable to Type I attacks, while the third one is susceptible to Type II attacks. To address these vulnerabilities, we propose a new CLASC scheme with enhanced security. It not only resists Type I and Type II attacks in the random oracle model but also achieves Girault’s Level-3 security. Finally, our experimental assessments demonstrate that the proposed scheme outperforms several recent CLASC schemes. It maintains similar computational costs and communication overheads compared to state-of-the-art CLASC schemes, while providing stronger security guarantees.