Researching a target with passive reconnaissance tools


There are many ways of performing recon online without ever going near a potential target. Attackers will take advantage of tools like the ones described in this article. If you're serious about thinking like an attacker, you can use these tools to do your own reconnaissance and determine how much of your data is exposed online. I encourage you to spend lots of time on the OSINT Framework site to gain a better understanding of the passive reconnaissance tools currently in use.


  1. "Indexing HTTPS Pages by Default":
  3. Sectigo:
  4. DNSDumpster:
  5. OSINT Framework:
  6. DNS History:
  7. 8086 Consultancy:
  8. Dehashed:
  9. Have I Been Pwned?:
  10. Notification at Have I Been Pwned?:
  11. "The 15 Biggest Data Breaches of the 21st Century":
  12. Dehashed Data Wells:

The Author

Chris Binnie is a Cloud Native Security consultant and coauthor of the book Cloud Native Security:

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