SANS Digital Forensics and Incident Response Blog

Security Intelligence: Introduction (pt 1)


As the focus on information security by the US Government heats up, you will likely see a lot of professionals writing more about topics that touch on information warfare. The same day I began writing this, I also found myself reading some of GreyLogic's excellent analysis on some current events, for example. And as I was enjoying a beer in between completing the outline of this series and beginning this entry, I was both encouraged and disappointed to see Richard Bejtlich writing on part of the subject I plan to cover in Part 2: encouraged that other thought leaders were very much in line with our approach, and disappointed that Richard once again beat me to the punch! Richard is a professional whom I respect greatly; I think you'll find our opinions on this topic very much complementary. Just as is the case for so many aspects of our young industry, many of the writings on these subjects form a Venn diagram interesting for both their similarities and differences. As students of this subject - and we are all students, whether formally or otherwise - I encourage you to read everything you can and form your own conclusions. As for why you are reading this in a forensics and incident response blog, while many have written about information warfare theory, I have seen scant information on how to apply it in a practical sense to computer security. While this series is not 'information warfare' per-se, it is most certainly a derivative domain. As you either know or will soon discover through your experiences in the field, intrusion cases can proceed quite differently based on the nature of the problem. Legal investigations, intrusions of opportunity, worms/viruses, and sophisticated adversaries all quickly fork in their progression, although the tools used by investigators may remain the same. This is my effort to infuse my research and experience (and that of my team) in combating sophisticated adversaries into the SANS educational framework. I hope you enjoy and learn from it.

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Security Intelligence

What is security intelligence? SI is a recognition of the evolution of sophisticated adversaries, the study of that evolution, and the application of this information in an actionable way to the defense of systems, networks, and data. In short, it is threat-focused defense, or as I occasionally refer to it, intelligence-driven response. You will see in the coming installments how this is manifested in a practical way, and how some specific examples can be applied.


Definitions are important, and terminology in such a young field can vary. For the purposes of this series, I use the definitions given below. Whatever vernacular you choose to use in your professional career, the most important thing to remember is that you should use the terms consistently.

CND - Computer Network Defense. The act of defending computers and data from compromises of confidentiality, integrity, or availability, facilitated by other networked computers, and the subsequent response when such a compromise occurs.

CNE - Computer Network Exploitation, or alternately, Computer Network Espionage. The act of compromising computers for the purposes of gaining access to or modifying data, facilitated by remote access via computer networks. In short, compromises of integrity or confidentiality.

CNA - Computer Network Attack. The act of adversely impacting the availability of data or functionality of networked computer systems.

APT - Advanced, Persistent Threat. I first heard this term used by the USAF's 8th Air Force in a small meeting in 2006. Unless contradicting evidence is brought to bear on the subject, I give them credit for coining this term, which is any sophistcated adversary engaged in information warfare in support of long-term strategic goals.

TTP - Tactics, Techniques, and Procedures. Methodology, in this case of CNE, CND, or CNA.

Evolving Thought on Network Defense and Security

In order to address the risks posed by APT actors, an evolution in thought on both net defense as well as security writ large is needed. Security Intelligence is an effort by my team and I to that end. Please keep in mind that this is a recursive process of definition and implementation, trial and error, discussion and peer review. I feel that this series brings us close to some answers, but many open questions on this topic will remain, and this exploration still needs broader peer review.

Apart from the simple lack of brain cycles that have been applied to combating APT actors, another major obstacle to success is refocusing what is an increasingly myopic and misinformed vision of information warfare and security. If I hear "cyber 9/11," "cyber Pearl Harbor," "cyber Katrina," or "cyber <calamity>" one more time, I'm going to scream. Besides the word "cyber" having no real meaning, these terms are pure hyperbole and do not map in any way, shape, or form to the exigent sophisticated threat environment. I know this not just from my own personal experience, but by looking at the world around me with a trained eye. By far and away, the goals of the most sophisticated adversaries in 2009 are focused on the surreptitious acquisition of sensitive information for the purposes of competitive economic advantage, or to counter, kill, or clone the technologies of one's nation-state adversaries. No doubt, there are exceptions. While I believe the Estonian incident and recent spate of DDoS's received far more press than they deserved, they were nevertheless notable in highlighting CNA's emergent role in open, potentially armed conflict. But I would argue that their overall economic and long-term impact has likely been dwarfed by the continuous deluge of CNE operations impacting organizations.

Yet, the focus of the media (and to a degree our profession) has been on CNA - "the power grid", SCADA systems, wall street... yes, these are juicy targets for an adversary bent on open conflict, but the impact of such CNA operations would almost certainly lead to some sort of 'kinetic' response. While worthy of attention, these are nevertheless movie-plot threats that take a backseat to the chronic issues we are dealing with - nearly all of which are CNE in nature. To underscore my point, I took a highly scientific poll (*cough*): articles on "cyber attack" outnumber "cyber espionage" better than 6-to-1.

As a colleague remarked to me the other day, we do not refer to 9/11 as "plane terrorism," nor do we refer to the Oklahoma City bombing as "truck terrorism." Yet this is how many people think about CNA and CNE. Why? Any CNA or CNE operation is part of a broader effort to achieve some strategic, competitive goal. It is a tool, just as a truck bomb is a tool to instill terror. And, while we're here, the last thing I want to hear is anything about "cyber terrorism." There is simply no way that a simultaneous failure of all DNS root name servers, for instance, could evoke the same kind of fear as watching two of the world's largest buildings collapse. The goals achieved by CNA are many, but instilling fear in a whole population is not one of them. But I digress...

The bottom line is that in order for progress to be made, there needs to be an evolution in thought on APT actors by the media and, most importantly, the information security industry. First, the line between CNE and CNA is often blurred. Read any recent article about hackers stealing data, and you'll see an immediate tendency on the part of writers and interviewees to slide to these unrelated Hollywood CNA scenarios that do not at all map to the goals of the adversaries discussed therein. And please people, the answers lie not in patching systems, anti-virus, or user education. These strategies are necessary, but insufficient as they do not always map directly to the threat environment. Compromises by APT actors often do not happen because of some security failure that can be addressed with an easily-branded compliance strategy. They happen because adversaries are sophisticated, have extensive knowledge of their target, and are not discouraged by failure. Compromises, even in properly-secured environments, are inevitable - and the blame lies not with the victim. We must therefore focus efforts on raising the bar, introducing friction in an attack progression, earlier detection of attacks, and the ensuing response.

Based on feedback, I have split this introduction into 2 parts. The next part, which will be posted tomorrow, will discuss risk, where to apply SI techniques, and outline the rest of the series.


Posted July 22, 2009 at 12:53 PM | Permalink | Reply


Apologies for the formatting, everyone, I'm not sure what happened. We'll see if we can fix it to make this blob of text a bit more readable''

Posted September 21, 2010 at 3:19 PM | Permalink | Reply

Price K.

Useful write up. Interesting differentiation between CNA and CNE.

Posted March 24, 2011 at 1:26 PM | Permalink | Reply

Steve M.

Super late comment: good read. I've found that the term APT is applied quite liberally. I generally try to think about APT/CNE incidents as those that try to exfiltrate data, whereas the CNA incidents are those that try to break stuff. Maybe that's overly simplistic, but it works for the lay person.

Posted July 1, 2011 at 5:32 PM | Permalink | Reply

Mark Wireman

Good article. The one comment I'll make is as it relates to the following statement: "The goals achieved by CNA are many, but instilling fear in a whole population is not one of them." I disagree. While what we have been hearing of in the press and other forms of information outlets highlight that APT is attemping to compromise information, there are groups out there that are looking for a CNA to compromise a Gov't, Financial, Transportation, or Energy (Nuclear and non-Nuclear) network for the sole purpose of instilling fear in the population by showing they are in control and, unless we adhere to whatever demands they claim, the population will suffer. Whether this suffer is in the form of hardship, sociel disruption, or other means, the goal is to create fill and instill panic and chaos. Groups looking to inflict harm know how dependent developed Nations are on the electronic means of providing critical infrastructure and gov't services, making it the prized target for compromis and instilling fear in the minds of the society.

Posted January 14, 2014 at 2:44 PM | Permalink | Reply

Myke Cole

Per Joint Pub. 3-13 (has JP 3-13 been superseded? If so, I apologize), these are not the definitions for CNA, CNE and CND. I agree that definitions are important, and the military coined the idea of CNO to translate specific kinetic effects into cyberspace. I understand that you are changing the definitions to suit a different arena, but I encourage you to at least mention this to your readers. The idea of intel driven operations (which is the baseline for your position) is also originally a military concept, and one that is still in the process of translation into the cyber domain.
I hope this isn't coming across as pedantic. It's not intended to be. I'm just trying to hammer your initial point: definitions are important.

Posted January 18, 2014 at 9:28 AM | Permalink | Reply


Regarding your statement "And please people, the answers lie not in patching systems, anti-virus, or user education." for internal large scale systems as we see in private clouds, and clusters, what would you recommend as a defensive mechanism? the overhead and time to apply an update, some solutions can not be updated due to kernel customisations for specific hardware not easy to update. commercial solution tied to hardware, and certain software packages. would SI mean to accept that CNE will happen, and defeating it is not in the first knots of the kill-chain but the later stages?