After the outbreak of COVID-19, the risk of privacy leakage is increasing      At the beginning of 2020, the sudden outbreak of the COVID-19 pandemic brought a huge impact on everyoneâs work and life. On the one hand, the working-from-home scenario has pushed the development of digital office. Many companies have had to transfer the materials and assets from offline to online within a short time. On the other hand, to meet the demands of the public health and pandemic control, personal health data is collected and processed digitally to be used in areas like pandemic prevention and control, health services, and tracing inquiries. For instance, travel health codes have been used in countries like China and Spain for COVID-tracing, and many countries around the world have provided the online services of test appointment and test results inquiries. The outbreak of the COVID-19 pandemic has inspired people to rethink the construction and development of infrastructures. The large scale of data transmission and exchange during the pandemic period requires the support from new technologies. In the global context, in order to adapt to the ever-increasing demand for data exchange and promote the digitalization process, many countries have prioritized and invested on cutting-edge technologies like 5G, Big Data, Artificial Intelligence, Cloud Computing, etc.