Improved bounds for the implicit factorization problem

We study the problem of integer factoring with implicit hints. This problem is described as follows: Let $N_{1}=p_{1}q_{1},\dots,N_{k}=p_{k}q_{k}$ be $k$ different RSA moduli of same bit-size, where $q_1,\dots,q_k$ are of the same bit-size too. Given the implicit information that $p_{1},\dots,p_{k}$ share some certain portions of bit pattern, under what condition is it possible to factorize $N_{1},\dots,N_{k}$ efficiently? This problem has been studied in many references recently and many interesting results have been obtained. In this paper, we modify the previous algorithm presented by Sarkar and Maitra (IEEE TIT 57(6): 4002-4013, 2011). We show that our result achieves an improved generalized bounds in the cases where $p_{1},\dots,p_{k}$ share some amount of 1) most significant bits (MSBs); 2) least significant bits (LSBs); 3) MSBs and LSBs together. As far as we are aware, our result is better than all known results.