The paper proposes and substantiates approaches to building a corporate system for monitoring and analyzing social media on cybersecurity issues, which are based on the concept Big Data, Data/Text Mining, Information Extraction, Complex Networks, and Cloud Computing. The components of Elastic Stack technology, Sphinx information retrieval system, Graph Data Base Management System Neo4j, and Gephi graph analysis system are examined in detail. The main idea of a system for analyzing large amounts of data on cybersecurity issues from social media is the simultaneous application of methods and means of information retrieval, data analysis, and aggregation of information flows. The system should ensure the implementation of the following functions: the formation of databases by collecting information from certain information resources; settings for automatic scanning and primary processing of information from websites and social networks; maintaining full-text information databases; identifying duplicates similar in content to informational messages; full-text search; analysis of text messages, determination of tonality, the formation of analytical reports; integration with geographic information system; data analysis and visualization; study of the dynamics of thematic information flows; predicting developments based on the analysis of the dynamics of the publication in social media; providing access for many users to the functional components of the system. The practical significance of the results is to create a working layout of the content monitoring and analysis system of social media on cybersecurity issues, ready to be used as a component in information and cybersecurity decision support systems. The interface of the system layout is considered, in which the functions of search, analysis, and forecasting of information appearance in social media are available. Central to the interface is a digest of the most relevant user needs. In the analytical mode, a number of tools are implemented for graphical presentation of the analyzed data, which are displayed as a time series of the number of relevant queries per day, as well as viewing the main topics, clusters grouped by predefined reference words. The system provides modes for forming networks of concepts that correspond to individual messages (persons, brands) and information sources that allow you to rank the concepts and explore the relationships between them.