Fully Homomorphic Encryption with Chosen-Ciphertext Security from LWE

Rupeng Yang; Zuoxia Yu; Willy Susilo

Paper 2026/1756

Fully Homomorphic Encryption with Chosen-Ciphertext Security from LWE

Rupeng Yang

, University of Wollongong

Zuoxia Yu, University of Wollongong

Willy Susilo, University of Wollongong

Abstract

We construct (1-hop) fully homomorphic encryption (FHE) schemes with chosen-ciphertext (CCA) security from the learning with errors (LWE) assumption in the standard model. Security of our construction only relies on the circular-secure LWE, which matches the assumptions needed for FHE with the basic chosen-plaintext security. Besides, the scheme achieves a security notion that is strictly stronger than the CCA1 security. Prior FHE schemes with even just CCA1 security require either the random oracle model or non-falsifiable assumptions. The construction follows the well-known Naor-Yung double encryption paradigm. However, unlike previous works [Boneh et al., ITCS 2012; Canetti et al., PKC 2017; Manulis and Nguyen, Eurocrypt 2024], which employ general zero-knowledge succinct non-interactive arguments of knowledge (ZK-SNARKs), we design a special succinct argument to prove the validity of FHE ciphertexts. The succinct argument is constructed from batch arguments for NP and a new primitive called predicate extractable commitment, which may be of independent interest.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: A major revision of an IACR publication in CRYPTO 2025
Contact author(s): orbbyrp @ gmail com
History: 2026-08-22: approved; 2026-08-21: received; See all versions
Short URL: https://ia.cr/2026/1756
License: CC BY

BibTeX

@misc{cryptoeprint:2026/1756,
      author = {Rupeng Yang and Zuoxia Yu and Willy Susilo},
      title = {Fully Homomorphic Encryption with Chosen-Ciphertext Security from {LWE}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2026/1756},
      year = {2026},
      url = {https://eprint.iacr.org/2026/1756}
}