On the Security of Two IKKR-type Code-Based Cryptosystems

Kirill Vedenev

Paper 2025/674

On the Security of Two IKKR-type Code-Based Cryptosystems

Kirill Vedenev

, Southern Federal University

Abstract

The paper analyzes the security of two recently proposed code-based cryptosystems that employ encryption of the form $y = m G_{pub} + e E_{p u b}$ : the Krouk-Kabatiansky-Tavernier (KKT) cryptosystem and the Lau-Ivanov-Ariffin-Chin-Yap (LIACY) cryptosystem. We demonstrate that the KKT cryptosystem can be reduced to a variant of the McEliece scheme, where a small set of columns in the public generator matrix is replaced with random ones. This reduction implies that the KKT cryptosystem is vulnerable to existing attacks on Wieschebrink's encryption scheme, particularly when Generalized Reed-Solomon (GRS) codes are used. In addition, we present a full key-recovery attack on the LIACY cryptosystem by exploiting its linear-algebraic structure and leveraging distinguishers of subcodes of GRS codes. Our findings reveal critical vulnerabilities in both systems, effectively compromising their security despite their novel designs.

Metadata

Available format(s): PDF
Category: Attacks and cryptanalysis
Publication info: Preprint.
Keywords: Code-based cryptography Key-recovery attack Reed-Solomon codes Schur-Hadamard product
Contact author(s): vedenevk @ gmail com
History: 2025-04-15: approved; 2025-04-14: received; See all versions
Short URL: https://ia.cr/2025/674
License: CC BY

BibTeX

@misc{cryptoeprint:2025/674,
      author = {Kirill Vedenev},
      title = {On the Security of Two {IKKR}-type Code-Based Cryptosystems},
      howpublished = {Cryptology {ePrint} Archive, Paper 2025/674},
      year = {2025},
      url = {https://eprint.iacr.org/2025/674}
}