给出了RSA密码算法的一种类循环攻击算法.记RSA算法的公钥为(e,N),私钥为d.若存在正整数k,使得整数ek和整数dkmod(N)都较小,则基于一些已有的低解密指数攻击方法,可将RSA模数N的分解问题转化为RSA的公私钥方程的小根问题,从而可在多项式时间求解.实验数据表明,本方法可以找出RSA新的弱密钥. A round robin attack algorithm based on RSA cryptosystem is given. The public key of RSA algorithm is (e, N) and the private key is d. If there is a positive integer k, the integer ek and integer dkmod (N) , Based on some existing low-decryption index attack methods, the decomposition of RSA modulo N can be transformed into the small root problem of RSA’s public-private key equation so that it can be solved in polynomial time. The experimental data show that this method can find out RSA new weak key.