Domain OSINT and Attack Surface Mapping Using DNSDumpster

DNSDumpster Web Interface

Greetings everyone. In this blog post, I would like to walkthrough with you on DNSDumpster. DNSDumpster is an online tool designed for domain research, particularly useful for OSINT researchers, security professionals and penetration testers. It allows users to discover hosts associated with a specific domain, getting an insight of an organization's attack surface. This capability is crucial for effective security assessments, allowing defenders to perform passive reconnaissance and inform their information security strategies.

Example of Domain Search Result

DNSDumpster operates by leveraging open-source intelligence (OSINT) resources instead of relying on brute force methods commonly used in many DNS reconnaissance tools. DNSDumpster compiles data from various reputable sources, including the Alexa Top 1 Million sites, Search Engines, Common Crawl, Certificate Transparency, and more. This approach allows it to uncover hard-to-find subdomains and web hosts that might otherwise go unnoticed.

Attack Surface Mapping Using DNSDumpster 

One of the unique features of DNSDumpster is its ability to map an organization's attack surface through a process referred to as "dumpster diving." This term highlights the practice of extracting valuable information from seemingly discarded data, which in this context translates to sifting through DNS records to identify potential vulnerabilities. 

Banner Search Example

DNSDumpster allows banner search based the TCP ports 21, 22, 23, 80, 443 and 8080 as they are common services, with banners that often reveal operating system and other useful data.

Drilling Down the Domain and Subdomain Details 

It also allows you to download your search results as .xlsx, export as PNG format or view the graph as. HTML format. The platform is managed by Hackertarget.com, which also offers additional tools like Domain Profiler. This tool provides even more extensive data discovery capabilities based on user membership plans. The basic access to DNSDumpster remains free but you may need to subscribe premium membership to unlock further functionalities and unlimited subdomain results.

For security experts, using DNSDumpster can streamline vulnerability assessments and enhance overall security posture by identifying potential entry points for attackers. Its integration into the reconnaissance phase of security testing can save time and reduce the complexity often associated with gathering domain-related intelligence.