Paper 2013/123

Analysis and Improvement of Lindell's UC-Secure Commitment Schemes

Olivier Blazy, Céline Chevalier, David Pointcheval, and Damien Vergnaud


In 2011, Lindell proposed an efficient commitment scheme, with a non-interactive opening algorithm, in the Universal Composability (UC) framework. He recently acknowledged a bug in its security analysis for the adaptive case. We analyze the proof of the original paper and propose a simple patch of the scheme. More interestingly, we then modify it and present a more efficient commitment scheme secure in the UC framework, with the same level of security as Lindell's protocol: adaptive corruptions, with erasures. The security is proven in the standard model (with a Common Reference String) under the classical Decisional Diffie-Hellman assumption. Our proposal is the most efficient UC-secure commitment proposed to date (in terms of computational workload and communication complexity).

Available format(s)
Cryptographic protocols
Publication info
Published elsewhere. Unknown where it was published
UC Commitment
Contact author(s)
olivier blazy @ rub de
2013-03-05: received
Short URL
Creative Commons Attribution


      author = {Olivier Blazy and Céline Chevalier and David Pointcheval and Damien Vergnaud},
      title = {Analysis and Improvement of Lindell's UC-Secure Commitment Schemes},
      howpublished = {Cryptology ePrint Archive, Paper 2013/123},
      year = {2013},
      note = {\url{}},
      url = {}
Note: In order to protect the privacy of readers, does not use cookies or embedded third party content.