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Efficient Proofs of Possession for Legacy Signatures (Woo, Ozdemir, Sharp, Pornin, Grubbs 2025)

Last modified: 2026-10-27

DOI: 10.1109/sp61157.2025.00080 · URL: https://eprint.iacr.org/2025/538

Summary

Brings zero-knowledge proofs of possession of a message and signature close to practicality for widely deployed legacy schemes (RSA, ECDSA, Ed25519) by encoding signature verification as R1CS and optimizing it for a zkSNARK backend. Published at IEEE S&P 2025. BL26-SoK-AnonCreds lists it with FS24-Longfellow and PPZ24-Crescent as the recent works enabling ZKPs over ECDSA-signed data in a few seconds, and as an option for proving an ECDSA device-binding signature.

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