For a change of pace today Iam presenting a guest diary. This diary provides a brief summary of work done by Andrew Hunt, a recent GIACGold Paper author. His paper, Visualizing the Hosting Patterns of Modern Cybercriminals, is currently featured in the SANSInfoSec Reading Room. It describes tools and techniques that can be used to mine and visualize DNSinformation to aid in analyzing and potentially blocking malicious traffic. His work builds on work done by Chris Lee of Georgia Tech and fellow handler Bojan Zdrnja of University of Auckland.
Criminals operating on the Internet face little recourse for their actions. Hosted IP addresses are inexpensive and easy to acquire. Domain names are trivial to register and change. However, criminals are like most business people, pursuing the most efficient path to profit with the least amount of reinvestment. This indicates that their patterns of hosting may be mapped, and perhaps even predicted.
When passive authoritative domain query responses, cached BGP data, and geolocation information are married together, it becomes apparent that malicious hosters employ the same techniques as their legitimate counterparts to maximize profits: shared services, redundancy, favored service providers and favored jurisdictions. Visualizing these commonalities can intimate the repuation of services from the macro ASN to micro IP layers. Having this information combined with the typical access patterns and policies of their organization, an anlayst can make a more appropriate decision as to what actions are most effective to deal with an identified threat and its potential relations.
For example when seed data pulled from Malware Domains is correlated with passive DNS and ASN data, then visualized, it is possible to see how the majority of the authoritative nameservers are hosted in the same network block. This dependence indicates an investment by the aggressor into a particular hosting company and can provide an effective network-level block at relatively low cost. As always, be aware of potential collateral damage when blocking a network portion that may also contain legitimate IP hosting space.
If you are interested in more information on how this analysis was performed please see the full version of the paper, Visualizing the Hosting Patterns of Modern Cybercriminals at the SANS Reading Room.
-- Rick Wanner - rwanner at isc dot sans dot org - http://namedeplume.blogspot.com/ - Twitter:namedeplume (Protected)
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