arXiv subjects

Vitaliĭ Roman'kov

Publications and source records attributed to Vitaliĭ Roman'kov.

4 recordsLinked to original sources

arXiv2018

Cryptographic analysis of the Modified Matrix Modular Cryptosystem

We show that the Modified Matrix Modular Cryptosystem proposed by S.K. Rososhek is not secure against the attack based on the linear decomposition method. The security of the encryption scheme in the Rososhek's system is based on the mix of the conjugacy search problem and random "salt". We do not solve the conjugacy search problem and we are not looking for the exact meaning of the "salt". The transported secret message in the system is recovered without computation the secret parameters, that have been used for its encryption.

cs.CR↗

arXiv2015

$p$-solvability of regular equations over unitriangular groups over prime finite fields

An equation over a group with one unknown is called regular if the exponent sum of the unknown is nonzero. In this paper we prove that some regular equations of exponent $rp^s$, where $r \in \mathbb{Z}$, $s \in \mathbb{N}$, $\gcd(r,p)=1$, over the group UT$_n(\mathbb{F}_p)$ ($n \geq 2$) are solvable in an overgroup isomorphic to UT$_{(n-1)p^s + 1}(\mathbb{F}_p)$. Applying this for $n=3$ we prove that any regular equation of exponent $rp^s$ over the Heisenberg $p$-group UT$_3(\mathbb{F}_p)$ is solvable in an overgroup isomorphic to UT$_{2p^s + 1}(\mathbb{F}_p)$. The proofs of these results are constructive and allow to obtain solutions of equations in explicit form.

math.GR↗

arXiv2015

Adjunction of roots to unitriangular groups over prime finite fields

In this paper we study embeddings of unitriangular groups UT$_n(\mathbb{F}_p)$ arising under adjunction of roots. We construct embeddings of UT$_n(\mathbb{F}_p)$ in UT$_m(\mathbb{F}_p)$, for $n \geq 2$, $m=(n-1)p^s + 1$, $s \in \mathbb{Z}^+$, such that any element of UT$_n(\mathbb{F}_p)$ has a $p^s$-th root in UT$_m(\mathbb{F}_p)$. Also we construct an embedding of the wreath product UT$_n(\mathbb{F}_p) \wr C_{p^s}$ in UT$_m(\mathbb{F}_p)$, where $C_{p^s}$ is the cyclic group of order $p^s$.

math.GR↗

arXiv2015

Linear decomposition attack on public key exchange protocols using semidirect products of (semi)groups

We show that a linear decomposition attack based on the decomposition method introduced by the author works by finding the exchanged secret keys in all main protocols using semidirect products of (semi)grops proposed by Kahrobaei, Shpilrain, Habeeb, Koupparis and Lam.

cs.CR↗