The rapid advancement of cloud computing services necessitates stronger data security measures to protect sensitive information. This paper introduces a novel lightweight cryptographic algorithm aimed at enhancing data security in cloud environments, leveraging elliptic curve cryptography (ECC) for key generation. The proposed approach employs a double encryption method. In the first layer, logical operations such as XOR, XNOR, shifting, and swapping, based on Shannon’s principles of diffusion and confusion, are applied to partition the plaintext and key. The second layer further increases encryption complexity using a Feistel structure combined with substitution–permutation architecture, ensuring robust security. ECC is employed to generate strong, compact keys that offer improved security and efficiency compared to traditional key generation methods. Experimental results show that the proposed cryptographic model achieves significant improvements in encryption and decryption times, with an average encryption time of 1.974 s, decryption time of 1.371 s, and maximum processing time of 0.455 s. The proposed method outperforms conventional algorithms such as AES, DES, and Blowfish, offering superior security and performance in cloud computing environments.