Applied Threat Intelligence: Building a TI Program
As we wrap up our Applied Threat Intelligence series, we have already defined TI and worked our way through a number of the key use cases (security monitoring, incident response, and preventative controls) where TI can help improve your security program, processes, and posture. The last piece of the puzzle is building a repeatable process to collect, aggregate, and analyze the threat intelligence. This should include a number of different information sources, as well as various internal and external data analyses to provide context to clarify what the intel means to you. As with pretty much everything in security, handing TI is not “set and forget”. You need to build repeatable process to select data providers and continually reassess the value of those investments. You will need to focus on integration; as we described, data isn’t helpful if you can’t use it in practice. And your degree of comfort in automating processes based on threat intelligence will impact day-to-day operational responsibilities. First you need to decide where threat intelligence function will fit organizationally. Larger organizations tend to formalize an intelligence group, while smaller entities need to add intelligence gathering and analysis to the task lists of existing staff. Out of all the things that could land on a security professional, an intelligence research responsibility isn’t bad. It provides exposure to cutting-edge attacks and makes a difference in your defenses, so that’s how you should sell it to overworked staffers who don’t want yet another thing on their to-do lists. But every long journey begins with the first step, so let’s turn our focus to collecting intel. Gather Intelligence Early in the intelligence gathering process you focused your efforts with an analysis of your adversaries. Who they are, what they are most likely to try to achieve, and what kinds of tactics they use to achieve their missions – you need to tackle all these questions. With those answers you can focus on intelligence sources that best address your probable adversaries. Then identify the kinds of data you need. This is where the previous three posts come in handy. Depending on which use cases you are trying to address you will know whether to focus on malware indicators, compromised devices, IP reputation, command and control indicators, or something else. Then start shopping. Some folks love to shop, others not so much. But it’s a necessary evil; fortunately, given the threat intelligence market’s recent growth, you have plenty of options. Let’s break down a few categories of intel providers, with their particular value: Commercial: These providers employ research teams to perform proprietary research, and tend to attain highly visibility by merchandising findings with fancy exploit names and logos, spy thriller stories of how adversary groups compromise organizations and steal data, and shiny maps of global attacks. They tend to offer particular strength regarding specific adversary classes. Look for solid references from your industry peers. OSINT: Open Source Intelligence (OSINT) providers specialize in mining the huge numbers of information security sources available on the Internet. Their approach is all about categorization and leverage because there is plenty of information available free. These folks know where to find it and how to categorize it. They normalize the data and provide it through a feed or portal to make it useful for your organization. As with commercial sources, the question is how valuable any particular source is to you. You already have too much data – you only need providers who can help you wade through it. ISAC: There are many Information Sharing and Analysis Centers (ISAC), typically built for specific industries, to communicate current attacks and other relevant threat data among peers. As with OSINT, quality can be an issue, but this data tends to be industry specific so its relevance is pretty well assured. Participating in an ISAC obligates you to contribute data back to the collective, which we think is awesome. The system works much better when organizations both contribute and consume intelligence, but we understand there are cultural considerations. So you will need to make sure senior management is okay with it before committing to an ISAC. Another aspect of choosing intelligence providers is figuring out whether you are looking for generic or company-specific information. OSINT providers are more generic, while commercial offerings can go deeper. Though various ‘Cadillac’ offerings include analysts dedicated specifically to your organization – proactively searching grey markets, carder forums, botnets, and other places for intelligence relevant to you. Managing Overlap With disparate data sources it is a challenge to ensure you don’t waste time on multiple instances of the same alert. One key to determining overlap is an understanding of how the intelligence vendor gets their data. Do they use honeypots? Do they mine DNS traffic and track new domain registrations? Have they built a cloud-based malware analysis/sandboxing capability? You can categorize vendors by their tactics to help you pick the best for your requirements. To choose between vendors you need to compare their services for comprehensiveness, timeliness, and accuracy. Sign up for trials of a number of services and monitor their feeds for a week or so. Does one provider consistently identify new threats earlier? Is their information correct? Do they provide more detailed and actionable analysis? How easy will it be to integrate their data into your environment for your use cases. Don’t fall for marketing hyperbole about proprietary algorithms, Big Data analysis, or staff linguists penetrating hacker dens and other stories straight out of a spy novel. It all comes down to data, and how useful it is to your security program. Buyer beware, and make sure you put each intelligence provider through its paces before you commit. Our last point to stress is the importance of short agreements, especially up front. You cannot know how these services will work for you until you actually start using them. Many of these intelligence companies are startups, and might not be around in 3 or 4 years. Once you identify a set of core intelligence
