A Successful Subfield Lattice Attack on a Fully Homomorphic Encryption Scheme

Martha Norberg Hovd

Paper 2021/1626

A Successful Subfield Lattice Attack on a Fully Homomorphic Encryption Scheme

Martha Norberg Hovd

Abstract

We present the application of a known subfield lattice attack on a fully homomorphic encryption scheme based on NTRU. We show that the scheme is vulnerable to the attack due to a particular parameter having to satisfy a derived lower bound. We also show that, due to the structure of the scheme, the attack is successful in all practical instantiations of the scheme.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Published elsewhere. Minor revision. Norwegian Information Security Conference
Keywords: Fully homomorphic encryption lattices NTRU
Contact author(s): martha @ simula no
History: 2021-12-17: received
Short URL: https://ia.cr/2021/1626
License: CC BY

BibTeX

@misc{cryptoeprint:2021/1626,
      author = {Martha Norberg Hovd},
      title = {A Successful Subfield Lattice Attack on a Fully Homomorphic Encryption Scheme},
      howpublished = {Cryptology {ePrint} Archive, Paper 2021/1626},
      year = {2021},
      url = {https://eprint.iacr.org/2021/1626}
}