Abstract: Modern society are facing mounting cybersecurity risk. As one of the main means to maintain the spatial and temporal reference, GNSS is the essential component to cyberspace applications. Also the spatial and temporal data provided by GNSS is one of the most important information applied in the network. Vulnerability of GNSS contributes mostly to its security risk. When interfered, the GNSS devices lose its positioning capability or even output misleading information, threatening the security of GNSS applications or even that of the whole cyber-space. All-round countermeasures should be developed to safeguard the security of cyberspace, including the deepening of understanding, system development, technology advancing, and law enforcement.