On the security of Fiat-Shamir (FS) type signatures, some negative circumstantial evidences
were given in the non-programmable random oracle model (NPROM). Fischlin and …

We pose a question whether or not the standard RSA assumption is sufficient to prove the
security of the strong RSA-based (SRSA-based, for short) signatures. In this paper, we show …

Let $\Omega $ be a finite set of finitary operation symbols and let $\mathfrak V $ be a
nontrivial variety of $\Omega $-algebras. Assume that for some set $\Gamma\subseteq …

In recent years, Fischlin and Fleischhacker showed the impossibility of proving the security
of specific types of FS-type signatures, the signatures constructed by the Fiat-Shamir …

Let Ω be a finite set of finitary operation symbols. We initiate the study of (weakly) pseudo-
free families of computational Ω-algebras in arbitrary varieties of Ω-algebras. A family (Hd …

In this article, we study the connections between pseudo-free families of computational Ω-
algebras (in appropriate varieties of Ω-algebras for suitable finite sets Ω of finitary operation …

論文抄録 Paillier, Vergnaud は, Schnorr 署名など特定の Fiat-Shamir 型署名 (Fiat-Shamir
変換によって得られる署名方式の総称) に対して, 標準モデル上での安全性証明が困難であること …