The rapid development of smart mobile terminals and wireless technology and its global popularity have made the public's life more inseparable from social networks. In the big data era environment, a large number of social software emerged, but due to technical and financial reasons, most of the social software does not meet the needs of users, the user's information security suffered a major crisis.

As early as 2013, CCTV's 3-15 party exposed that Apple apps and Android apps have more or less leaked user information during the software development process. From ancient times to the present, the issue of information security has been the concern of the people, information data involves daily life and citizens production and life related to a variety of data, which has a significant role.

In the era of big data, the public's information relies on computer technology to store and apply, which has a huge amount of information data, which also increases the chance of information leakage. This paper aims to analyze a series of reasons for information leakage, to provide the necessary constructive improvement for the protection of China's information in the era of big data, and tries to find preventive measures in the face of information leakage. The harm of information leakage in the era of big data With the rapid progress of China's scientific and technological level, computer technology has been popularized, which greatly improves the user's work efficiency, meets the needs of people's life and production in many aspects of the country's nationals are also more dependent on the computer.

However, computer technology brings people not only the convenience of life, there are also many information security risks, such as this do not pay attention to, will cause serious harm to our national production and life.

First, information leakage jeopardizes citizens' basic property rights. In daily life, the user information data leakage phenomenon is very common: the user receives the phenomenon of spam text messages has become commonplace, citizens often receive harassing phone calls to promote the goods, spam all over the world, and more seriously, the lawless elements through the use of purchased user information under false pretenses to run a card overdraft of the user's property, the use of user information to carry out financial fraud and so on. The leakage of user information gives lawbreakers an opportunity to take advantage of, affecting the normal life of citizens, and even threatening the safety of their lives and property.

Second, information leakage jeopardizes citizens' personal reputation. With the popularization of big data, people's reliance on computer technology has become stronger and stronger, and information leakage incidents occur frequently.On April 23, 2018, the New Beijing News exposed the illegal behavior of several takeaway platforms that leaked user information.On June 16, 2018, job search information involving 1.95 million users on the dark web was called for sale.In December 2018, 65,000 pieces of loan data on P2P platforms were sold at explicit prices. The leakage of such a huge amount of data poses a great threat to the production and life of our nationals. After the user information data was leaked, all the things done by the wrongdoers in the name of the user were all attributed to the victimized user, destroying the user's personal reputation.

Thirdly, information leakage makes related crimes easier. Due to the large-scale leakage of information data, lawbreakers are able to get hold of the detailed private information of the victim, they will have an in-depth understanding of the victim-related information before the implementation of criminal activities, planned and purposeful implementation of precise fraud on the victim. And because they have enough information about the victim, the victim is easy to believe the lies of criminals, resulting in irreparable economic losses. Compared to economic losses, the most fearful because of the personal injury caused by information leakage. In addition, the leakage of information data is likely to lead to the user's work, activities, itinerary, property information and other important private information stolen by outsiders. If this information falls into the hands of criminals, it will be impossible to predict the next step of the offender's plan as well as the target, which poses a great threat to the life safety of the victimized users.

Fourth, information leakage is difficult to manage. Information data has great commercial value, attracting a lot of criminals to join, and now has formed a high-tech "black industry chain". With the development of Internet technology, illegal access to information involved in the crowd can be cross-regional, cross-industry illegal activities, and with the development of computer technology, many criminals are mastering high-tech computer talent, which increases the difficulty of the government's special crackdown on the illegal trade in information and data behavior, illegal access to information is not effective control of the malpractice, or even more rampant, resulting in national information security The problem is very serious.