[Resource Topic] 2025/359: A Note on Zero-Knowledge Simulator of the CROSS Identification Protocol

Welcome to the resource topic for 2025/359

Title:
A Note on Zero-Knowledge Simulator of the CROSS Identification Protocol

Authors: Shai Levin

Abstract:

We point out flaw in zero-knowledge of the CROSS identification protocol, \textsf{CROSS-ID}, which allows a distinguisher to distinguish real and simulated transcripts given access to the witness. Moreover, we show that the real and simulated transcripts are not statistically indistinguishable, and therefore the protocol can only satisfy weak computational (rather than strong, statistical or perfect) Honest Verifier Zero-knowledge. This issue is still present in version 2.0 updated on January 31, 2025, which resolves the security losses attained via the attacks of [BLP+25]

ePrint: https://eprint.iacr.org/2025/359

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .