Research On Differential Analysis Of Two Image Encryption Algorithm Based On Chaotic

In the era of information,the Internet and online services have become so popular that users enjoy them without taking into account the security threats they pose.Digital images are widely used in commerce,military,medical care and other fields,and images are required to be transmitted and stored securely.In recent years,a large number of commercial,personal and government image data leakage highlights the importance of various types of image encryption.Chaotic system is widely concerned because of its unique randomness,ergodicity and sensitivity,and have been widely used in the field of image encryption.Recently,researchers have proposed a variety of image encryption schemes based on different chaotic systems and different encryption structures,but these encryption schemes show certain vulnerability in the face of all kinds of cryptanalysis methods.The purpose of cryptanalysis is to find the defects in the image encryption algorithm,so that the algorithm designers can improve the algorithm according to the defects,so as to increase the security of the encryption scheme.Therefore,it is of great significance to use cryptanalysis methods to analyze the security of image encryption algorithms based on chaos.In this paper,based on the chosen ciphertext attack conditions,two chaotic image encryption schemes proposed recently are analyzed,and the results show that none of the above schemes can withstand differential attacks.This article also analyzes and summarizes the deficiencies in the chaotic image encryption schemes proposed in recent years,and put forward targeted improvement suggestions.The specific results are as follows:1)The security analysis of the image encryption algorithm based on the twodimensional infinite collapse map designed by Cao et al.found that there are defects in the scheme,and then based on the idea of chosen ciphertext attack,differential cryptanalysis is carried out on the scheme,so that the attacker can recover the plain image without knowing the key.Finally,with the help of computer software simulation,the corresponding attack example is given to verify the correctness of the attack scheme.2)The security analysis of the image encryption algorithm based on CML mapping designed by Wang et al.found that there are security defects in the scheme.Then,a differential attack method was introduced to make the attacker find a fixed differential path with a certain probability without knowing the key,and the differential path is used to realize the recovery of the plain image.Finally with the help of computer software simulation,the corresponding attack examples are given3)to verify the correctness of the attack scheme,and the success rate of the attack scheme is analyzed.4)Analyze and summarize the security risks of the chaotic image encryption scheme with higher security among the existing schemes,and put forward some constructive suggestions for improvement.