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Server-Aided Anonymous Credentials (Chairattana-Apirom, Harding, Lysyanskaya, Tessaro 2025)

Last modified: 2026-10-27

URL: https://eprint.iacr.org/2025/513

Summary

Formalizes server-aided anonymous credentials (SAAC), where the holder, when showing a credential, is helped by auxiliary information obtained in an earlier anonymous interaction with the issuer. This enables publicly verifiable, multi-show anonymous credentials from pairing-free elliptic curves, compatible with existing national standards. Gives rigorous definitions and constructions from keyed-verification credentials and oblivious issuance, providing the formal footing that the EUDI wallet candidate BBS# lacked.

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