DNS describes the structure of resources on the internet. It can provide lots of valuable information about (attacker or target) infrastructure. However, in order to query DNS records, you must already know the exact domains or subdomains to query. When examining unknown infrastructure, this is not practical. On top of that, DNS records can change often, so historical information is lost. Passive DNS databases help solve both of these problems. Farsight Security DNSDB is the largest passive DNS database in the world. With DNSDB, you can answer questions like “How has this network infrastructure changed over time?”, “What other domains and subdomain point (or have pointed to) this IP address?”, “What are the subdomains and resource records for this domain?”
The Domain Name System (DNS) is best known as the way domain names are converted into IP addresses that clients connect to, but there are many other uses for DNS. Read on to learn more.