IJPAM: Volume 110, No. 4 (2016)




Normahirah Nek Abd Rahman$^1$, Muhammad Rezal Kamel Ariffin$^2$
$^{1,2}$Al-Kindi Cryptography Research Laboratory
Institute for Mathematical Research
Universiti Putra Malaysia
43400 UPM Serdang, Selangor, MALAYSIA
$^2$Department of Mathematics
Faculty of Science
Universiti Putra Malaysia
43400 UPM Serdang, Selangor, MALAYSIA


This paper proposes three new attacks on RSA with the modulus $N=p^{2}q$. The first attack is based on the equation $eX-NY=(p^{2}u+q^{2}v)Z$ such that $u$ is an integer multiple of $2$ and $v$ is an integer multiple of $3$ with $\vert{p^{2}u-q^{2}v}\vert< N^{1/2}$ and gcd$(X,Y)=1$. If $X\vert Z\vert<\frac{N}{2\vert p^{2}u+q^{2}v\vert}$, then $N$ can be factored in polynomial time using continued fractions expansion. For the second and third attack, this paper proposes new vulnerabilities in $k$ RSA cryptosystem moduli $N_{i}=p_{i}^{2}q_{i}$ for $k \ge 2$ and $i=1,...,k$. The attacks work when $k$ RSA public keys $(N_{i},e_{i})$ are related through $e_{i}x-N_{i}y_{i}=(p_{i}^{2}u+q_{i}^{2}v)z_{i}$ or $e_{i}x_{i}-N_{i}y=(p_{i}^{2}u+q_{i}^{2}v)z_{i}$ where the parameters $x$, $x_{i}$, $y$, $y_{i}$ and $z_{i}$ are suitably small.


Received: June 23, 2016
Revised: August 15, 2016
Published: November 9, 2016

AMS Classification, Key Words

AMS Subject Classification: 11A51, 11A55, 11K60, 03G10
Key Words and Phrases: RSA, factorization, continued fraction, LLL algorithm, simultaneous diophantine approximations

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How to Cite?

DOI: 10.12732/ijpam.v110i4.3 How to cite this paper?

International Journal of Pure and Applied Mathematics
ISSN printed version: 1311-8080
ISSN on-line version: 1314-3395
Year: 2016
Volume: 110
Issue: 4
Pages: 587 - 607

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