New algorithm subversion attack and cryptographic reverse firewall for identity-based signature

Jia, Sifan

doi:10.1016/j.sysarc.2026.103946

New algorithm subversion attack and cryptographic reverse firewall for identity-based signature

2026-08-01

0

PRE

AI

DOI：10.1016/j.sysarc.2026.103946

Original

Original request for help

Save

Abstract

En 中文

The revelations by Edward Snowden have significantly eroded trust in cryptographic standardization, highlighting the realistic threat of algorithm substitution attacks (ASA) where black-box implementations leak user secrets via undetectable backdoors. While cryptographic reverse firewalls (CRFs) for identity-based signature (IBS) have demonstrated their effectiveness in sanitizing randomness during operational phases like key extraction and signing, existing solutions typically rely on the strong assumption of a trusted Setup phase. An open problem remains in the literature: ASA attacks can occur at any stage of the IBS lifecycle (including Setup, Extract and Sign phases), yet existing CRF constructions for IBS only address limited scenarios of such attacks. In this paper, we present a new ASA and demonstrate that if the parameter generation process is compromised, an adversary can deterministically embed backdoors into public parameters to recover the master private key, rendering downstream firewalls ineffective. To mitigate this threat, we propose a new subversion-resistant IBS scheme. Our primary contribution is the design of a novel Reverse Firewall mechanism, which ensures the integrity and unbiasedness of system parameters without relying on a trusted authority. Formal security analysis confirms that our scheme effectively resists subversion attacks across the entire lifecycle.

Keywords:

Cryptographic reverse firewall

Identity based signature

Algorithm subversion attack

New algorithm subversion attack and cryptographic reverse firewall for identity-based signature

Abstract

Journal

Organization

Cited Papers