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SOC Analyst Pyramid

Introduction

Last weekend, I did a 10 minute fireside chat during lunch at BSidesSATX 2015 [1].  It was an informal presentation, where I discussed some of the issues facing security analysts working at an organization's Security Operations Center (SOC).

With only 10 minutes, the largest part of that presentation covered a "SOC analyst pyramid" of activity any organization will encounter.

For the presentation, security analysts are defined as people who monitor their organization's network for near-real-time detection of malicious activity.  Security analysts review alerts from their organization's intrusion detection systems (IDS) or security information and event management (SIEM) appliances.  These alerts are based on various sources, such as network traffic and event logs.

SOC Analyst Pyramid

Below is a visual representation of this pyramid:

As seen in the image above, the pyramid from top to bottom reads:

  • Targeted attacks
  • Malicious activity - not blocked
  • Malicious activity - blocked or not applicable
  • False positives or non-threat

Base of the SOC Analyst Pyramid

The base of the SOC analyst pyramid consists of false positives or valid activity unique to your organization's network.  In my years as an analyst, investigating this activity took up the majority of my time.  At times, you'll need to document why an alert triggers a false positive, so it can be filtered and allow the team to focus on real suspicious activity.

In my experience, no matter how well-tuned your security monitoring system is, analysts spend most of their time at this level of the pyramid.

Next Tier: Malicious Activity - Blocked or Not Applicable

The next level involves malicious activity that's either blocked or not applicable.  Blocked activity includes spam with malware attachments (malspam) blocked by your organization's spam filters.  Non-applicable activity includes certain types of scanning.  The intent is malicious, but the scans are blind and not applicable to the targeted host.  For example, here's a short list of activity from the error logs of a server I run:

That server doesn't run WordPress, nor does it have any sort of web-based administrative login, but I'll find WordPress-based scans hitting the server's IP every day.  That shows malicious intent, but it's not applicable.

SOC analysts worried about near-real-time detection of malicious activity generally don't spend much time with this tier of the pyramid.

Next Tier: Malicious Activity - Not Blocked

The next tier of the pyramid involves malicious activity that somehow makes it past your organization's various security measures. This level includes drive-by infections from an exploit kit after viewing a compromised website.  Depending on your organization's policies, adware might be an issue.  Resolving issues involving adware or potentially unwanted programs (PUP) might give SOC personnel practice for resolving hosts infected with actual malware.  Just make sure analysts don't focus on the adware/PUP.  The focus of a SOC should always be on malicious activity.

This level of the pyramid is where analysts develop their skill in recognizing malicious activity.  Exploit kit traffic might not infect a user's computer.  SOC personnel should be able to examine this sort of malicious traffic and determine if a host actually became infected.  After an alert, I've seen too many people assume a host was infected without digging in deeper to see what actually happened.

Malware or compromised hosts found at this level of the pyramid are not targeted.  This type of malicious activity is a concern for any organization.  It's not limited to your employer.

Top of the Pyramid: Targeted Attacks

This tier is where a SOC proves its value to an organization.  If bad actors, criminal groups, or hostile foreign agents gain a foothold in your organization's infrastructure, you might not be able to get rid of them.  Detecting intrusions early and preventing these bad actors from further access is extremely important.  Any number of sources will tell you data breaches are not a matter of "if" but "when" [2][3][4].

Targeted attacks include spear phishing attempts to gather login credentials from specific members.  Personnel using a chat system for sales or support can also be targeted.  Denial of Service (DoS) attacks or Distributed DoS (DDoS) attacks are usually at this tier.  Watering hole attacks [5] are also an issue.

Final Words

I've been a SOC analyst for two employers: one was the government, and the other is private sector.  In both cases, I believe the SOC analyst pyramid applies.  Feel free to leave a comment, if you have any opinions on the matter.

---
Brad Duncan, Security Researcher at Rackspace
Blog: www.malware-traffic-analysis.net - Twitter: @malware_traffic

References:

[1] http://www.securitybsides.com/w/page/91978878/BSidesSATX_2015
[2] http://www.securityinfowatch.com/article/12052877/preparing-for-your-companys-inevitable-data-breach
[3] http://www.maslon.com/webfiles/Emails_2015/LegalAlerts/2015_LegalAlert_CyberSecurity_DataBreach_webversion.html
[4] http://www.hechtins.com/blog/data_breach--not_if_but_when.aspx
[5] http://www.trendmicro.com.au/vinfo/au/threat-encyclopedia/web-attack/137/watering-hole-101

Brad

338 Posts
ISC Handler
Nice article

Although I think analysts cover some more domains like APT etc so better rename malicious word.
Anonymous
Thanks. I forgot to include advanced persistent Threat (APT) under the targeted attacks category. Of note, I've seen activity called APT that's more like an "average" persistent threat--not particularly advanced, but persistent.
Brad

338 Posts
ISC Handler
The article is indeed very insightful. I have been working as SOC analyst in a private sector for past 4 years and agree with the content.

We end up signing a customer and take over their un-tuned network and spend most of the time and cleaning up. Identifying actual attacks becomes like searching needle in a haystack. Also based on findings tuning is to be recommended. Sometimes the events gets missed and we all know what comes next.

I also like to have a check for baseline configurations when we signup new customers. Basic checks that identifies any violation of industry policies or standard for example outbound NTP traffic, use of default usernames etc...

I wanted to have this out as my GCIA Gold topic as a life as analyst in SOC. I am glad other big brains are thinking the same.
makflwana

17 Posts
You could also try a comparison with the Safety, Health and Environmental "safety triangle". This is an empirically proven correlation between minor incidents and a fatal accident. Example:

600 minors, such as "needed a Band-Aid" leads to

30 accidents requiring treatment by trained personnel leads to

10 serious accidents requiring transport to a hospital leads to

1 fatal accident.

http://crsp-safety101.blogspot.com/2012/07/the-safety-triangle-explained.html

If the relationship is not maintained, it generally means that people are under-reporting something, usually because of disciplinary threats for working in an unsafe manner.
Anonymous
Does anyone have enough metrics to translate the safety pyramid for security incidents? Would make for an interesting comparison.

Brent Eads, CISSP-ISSAP
A Fortune 100 Manufacturer
Beads

1 Posts
I like the pyramid. It seems to be the geometry of choice for SOC Analysts (thinking David Bianco and his pyramid of pain). I like to measure the effectiveness and maturity of the SOC analytical process on how quickly we can successfully identify a false positive and move on to "more interesting" work. Good people, quality tools and quick access to good data all help in reducing the base of the pyramid (Non-Threat) to a manageable state.

Michael
@chief_m1ke
Michael

1 Posts
Nice post.

One question: if SOC analysts do not spend time on the "malicious activity - blocked" tier, how does the SOC build intelligence surrounding the company's adversaries? Is that something that would be left to another team (not the SOC) or not something viewed as important at all?
Michael
1 Posts
Thanks! In my experience, that threat intelligence falls under a different team. I'd defined SOC Analysts as people focusing on near-real-time detection. Something like a threat research team is more appropriate to build your company-specific threat intelligence. That research team may or may not fall administratively under the SOC. If not, the team would still be working closely with the SOC.

Threat intelligence from blocked activity is certainly important. Organizations with a mature security structure would not ignore information from that tier.
Brad

338 Posts
ISC Handler
I do not, Brad. But I doubt it's physical safety specific. What's more important is the relationship between the numbers. At a former job, plant management was tired of all of the OSHA 300 records and decided to pay the unionized employees to become safer. Once the goal to reduce the minors was reached every employee got $50 a month until the numbers rose. It worked, sort of.

A new plant manager calculated the numbers for all of the tiers and discovered the bottom one was about half of what it should have been but the other three were right on target except the fatal had not occurred. So the number of incidents was the same except people were under-reporting to get the $50. And there was peer pressure to not report because either everyone got the $50 or no one did.

He held three plant-wide meetings, one per shift. He introduced the safety triangle and the current numbers. He told everyone to look at the person to their left and then at the person to their right. Then he said that the numbers said at least one of the people who were just looked at should be dead and if things did not change for real, one of the people would die soon. It really got people's attention and then he changed the metric to a total reduction, not just the bottom tier. People got it and within some months they all got their $50 again but this time with real numbers. And no one died and the hospital transports decreased etc.
Anonymous
I agree. The issues come at training analysts to dig deeper, and to having access for the analysts to check systems for signs of compromise. If the IDS alerts on the EK activity, but doesn't alert on post exploit activity and the host based AV didn't detect anything, does that mean (As far as the analyst knows) that the exploit wasn't succesful? How do we train analysts to detect post exploit activity.

In any case Brad, i'd like to hear about how an analyst progresses in their career.
SasK

12 Posts
How does an analyst progress in their career, you ask? A lot of it is personal initiative. The good analysts who progress have a natural curiosity and a drive to investigate. They desire to better know and understand network traffic.

Security analysts who investigate IDS events are people on the front line. Personnel-wise, a SOC will have more analysts than other positions, especially when you're looking at 24/7 coverage. Security analyst is a highly-skilled position, but somewhat basic in the overall scheme of SOC operations. In many organizations, these analysts also perform other security-related duties.

From what I've seen, career progression eventually leads out of the analyst position into something like a manager, security architect, threat researcher, and the like.
Brad

338 Posts
ISC Handler

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