Open-source intelligence (OSINT) is a critical tool for cybersecurity teams. It reveals sensitive information that attackers might have, helping cybersecurity professionals to anticipate and mitigate attacks and prioritize their security resources. It’s also a key component of penetration testing.

In addition to the OSINT email investigation public, social media and other online sources contain huge amounts of relevant data. Many cybercriminals use OSINT to retrieve personal and professional information about their targets, so that they can curate a targeted spear-phishing attack. This type of reconnaissance is usually conducted during the reconnaissance phase before an actual attack, which allows the hackers to get a better understanding of their target and plan the best way to breach their target’s organization.

How to Conduct OSINT Email Lookups Effectively

Many tools are available for conducting OSINT investigations, including free and paid options. For example, Shodan can reveal a variety of publicly available information, such as devices, vulnerabilities and associated network connections; Spyse can search websites and their owners; and specialized tools like Peepmail can decode the technical details of emails to discover hidden metadata.

While the use of OSINT in an investigation can help uncover valuable and damaging information, it’s important that cybersecurity professionals exercise caution. Some OSINT practices can cross the line into illegal hacking and eavesdropping, which can carry heavy penalties in the U.K. For instance, exposing private information about a person’s physical location or social connections without a clear, ethical justification can be a violation of privacy laws and can result in fines or jail time.