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Bulk WHOIS Lookup in Action: 5 Cybersecurity Use Cases by@WhoisXMLAPI

Bulk WHOIS Lookup in Action: 5 Cybersecurity Use Cases

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Top Whois, DNS, IP and threat intelligence data provider. We provide APIs, databases, and tools.

Around March last year, a report cited a record hike in zero-reputation domain registrations done in 24 hours with as many as 240,000 new domains registered that day. The organization noted that it was the highest number recorded over the past six months, representing a 36% increase from the 176,000-daily average.

Numbers like these are just an indication of how many domains cybersecurity specialists must be able to make sense of every day. Newly registered domains (NRDs), in particular, often figure in spamming, phishing, adware proliferation, and malware distribution. That’s the reason why companies must proactively learn about these domains and other ones then filter and block them where necessary. 

Yet doing so one domain at a time is simply unpractical. A service that comes in handy for gathering details about domains rapidly, both newly-registered and older ones, is Bulk WHOIS Lookup. In a nutshell, this bulk domain search tool allows users to retrieve WHOIS information on a large scale.

How Bulk WHOIS Lookup Helps Users

Bulk WHOIS Lookup is a web application that allows users to retrieve crucial data points for a list of domains. It's powered by over a decade of domain data gathering for close to 2900 TLDs and 600 million domains tracked, resulting in 7+ billion WHOIS records collected in total.

By uploading a Comma-Separated Values (CSV) file of domains, IP addresses, or email addresses to the tool, or inputting them directly as text, users can easily retrieve their WHOIS records.


Below are some areas where the product can prove beneficial.

1. Threat Hunting and Detection

Bulk WHOIS Lookup cuts the manual efforts required for security operations centers (SOCs) when investigating a large number of domain registrations potentially linked to targeted attacks. Some NRDs may appear benign, but their WHOIS records may indicate otherwise, even more so when they’re privacy protected.

2. Managed Detection and Response (MDR)

It’s possible to respond faster to threats when obtaining comprehensive WHOIS records for malicious domains in bulk. Security companies can quickly check whether domains entering their clients’ networks are likely to be dangerous with thorough WHOIS records derived from the tool. Anti-malware solutions and spam blocklist providers can also rely on the service to update their databases with current and accurate WHOIS data.

3. eDiscovery

Law enforcement, litigation experts, and security researchers can use Bulk WHOIS Lookup to procure digital evidence against cybercriminal gangs who often possess a large number of domains. Since attackers often share the same tools, tactics, and procedures (TTPs), users can rely on the product to identify emerging patterns in the WHOIS records of offending domains. Example indicators of guilt may include sudden name server or registrant changes, among others.

4. Fraud and Cybersquatting Prevention

Bulk domain searches also allow users to swiftly retrieve the ownership details of all the offending domains harvested via a reverse WHOIS query. In this case, cybersecurity specialists can first use any WHOIS record identifier such as a registrant name and run it into Reverse WHOIS Search to get a list of domain names sharing that identifier. From there, they can learn more about connected domains as well as retrieve their registrar and abuse contact details to inform relevant parties about potential misuses.

5. Third-Party Risk Assessment

Suppliers and software vendors are common entry points exploited by cyber attackers to reach their eventual targets. That is why companies often spend time thoroughly vetting potential business partners before sharing information with them or using their service. As part of this process, a bulk domain lookup tool is valuable as it allows gathering the registration details of various domain names at once and in a consistent format. In turn, this allows for the direct comparison and analysis of multiple third parties’ domains.

Overall, Bulk WHOIS Lookup is a potent cybersecurity tool that can help companies gather WHOIS information efficiently about both newly-registered and older domains and safeguard their networks and users from malicious properties.