Welcome to the resource topic for 2025/934
Title:
Diving Deep Into UC: Uncovering and Resolving Issues in Universal Composability
Authors: Céline Chevalier, Éric Sageloli
Abstract:Introduced by Canetti in 2001, Universal Composability (UC) is a widely adopted security model that enables the specification and proof of security for a broad range of protocols, offering strong security guarantees.
At its core lies the universal composition theorem (UC theorem), which ensures that protocols proven secure within the framework remain secure even when deployed in real-world environments with multiple instances of them.
In this work, we present two key contributions. First, we identify several problems with the UC framework, in particular the UC Theorem. They include counterexamples, limitations that make it unusable for important classes of protocols, and weaknesses in its proof. These problems reveal flaws in nearly all the fundamental concepts of UC.
Secondly, we update the main concepts of UC to address these problems. Although these revisions are nontrivial, our updated definitions are intended to stay as closely aligned with the original model as possible, while providing greater simplicity overall. To ensure the validity of these updates, we present a proof of the updated UC theorem, which is more detailed and modular than the original.
ePrint: https://eprint.iacr.org/2025/934
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 .