Data files, photos, and videos on the internet are vast sources of information about the person who posted them. These files contain content about appearance, behaviour, views, and material status. Analyzing these files helps verify the accuracy of the content and helps verify the creation method. Social media platforms like Facebook, Twitter, and Instagram often post this information. Public databases provide information about enterprises, corporations, and public figures, enabling access to government trips, scientific articles, and company reputations. These resources help in understanding potential collaborations and identifying potential partners. Open-source intelligence (OSINT) is a collection of tools and methods for extracting information from publicly available sources. It helps verify the accuracy and authenticity of information, as seen in the FBI's 2020 investigation of a Philadelphia woman involved in protests and preparing precise attacks like spear phishing. In this manuscript, we present an up-to-date overview of research that uses open-source methods and techniques. We will concentrate on the tools and methods advancing the cybersecurity industry. Studying the manuscript of OSINT opportunities and challenges can help readers understand the state of the art in theory and practice. We will also highlight the future directions and requirements for OSINT methods and the newly designed tools using these methods.