RT info:eu-repo/semantics/article
T1 SecureMD5: A new stream cipher for secure file systems and encryption key generation with artificial intelligence
A1 Herrera Montano, Isabel
A1 Ramos Diaz, Juan
A1 Molina Cardín, Sergio
A1 Guerrero López, Juan José
A1 García Aranda, José Javier
A1 Torre Díez, Isabel de la
K1 Encryption algorithm
K1 Encryption key generation
K1 Artificial intelligence
K1 Information security
K1 Insider threat
K1 33 Ciencias Tecnológicas
AB The insider threat to sensitive information posed by employees or partners of an organisation remains a majorcybersecurity challenge. In this regard, the measures taken by organisations and companies to protect infor-mation are often insufficient. Primarily, due to the legitimate access and knowledge of security holes that theseindividuals possess.This study proposes SecureMD5, an encryption algorithm designed specifically for secure file systems (SFS).The algorithm is based on custom one-way functions integrated into an encryption scheme that operates at thebyte level. It uses 11 dynamic variables generated from contextual parameters such as file position, access time,random values, and user-specific keys. This approach ensures that SecureMD5 does not inherit the known vul-nerabilities of MD5 as a standard cryptographic algorithm. Consequently, SecureMD5 is presented as an adaptiveand robust solution that addresses the challenges posed by insider threats in SFS.In parallel, a modular contextual key generation scheme is proposed, which can incorporate various challengessuch as user identity, access time and device location. Biometric key generation based on Artificial Intelligence(AI) methods is evaluated independently from the validation of the encryption algorithm. In the evaluatedbiometric key generation scheme, the AI models MediaPipe Hand Landmark and LBPHFaceRecognizer fromOpenCV have been used. These methods are part of a sub-key generation scheme based on contextual challenges.This scheme eliminates the need for key storage for dynamic and secure access to sensitive information.SecureMD5 was validated by diffusion, confusion, entropy and performance analysis. It achieved 31 % higherentropy than comparable algorithms. Performance improved by 0.32 % compared to RC4. It also passed 87 % ofNIST 800–22 tests, demonstrating its robustness against cryptographic vulnerabilities. In addition, SecureMD5balances security and performance, with encryption times 25 % faster than a modified AES algorithm for 10 MBfiles. Biometric key generation methods were evaluated using metrics such as precision, accuracy, false accep-tance rate and specificity, achieving satisfactory values above 80 % on all metrics. This work addresses criticalgaps in information security, providing significant advances in protecting SFS against insider threats. The designand adaptability of SecureMD5 make it particularly suitable for sectors with strict security requirements, such ashealthcare, finance, and corporate data management. Its ability to enable dynamic and secure access controladdresses the real challenges posed by protecting confidential information from internal threats.
PB Elsevier
SN 0920-5489
YR 2026
FD 2026
LK https://uvadoc.uva.es/handle/10324/78513
UL https://uvadoc.uva.es/handle/10324/78513
LA eng
NO Computer Standards & Interfaces, 2025, vol. 95, p. 104047
NO Producción Científica
DS UVaDOC
RD 31-oct-2025