Threat Detection Evolution: Why Evolve? [New Series]By Mike Rothman
As we discussed recently in Network-based Threat Detection, prevention isn’t good enough any more. Every day we see additional proof that adversaries cannot be reliably stopped. So we have started to see the long-awaited movement of focus and funding from prevention, to detection and investigation. That said, for years security practitioners have been trying to make sense of security data to shorten the window between compromise and detection – largely unsuccessfully.
Not to worry – we haven’t become the latest security Chicken Little, warning everyone that the sky is falling. Mostly because it fell a long time ago, and we have been working to pick up the pieces ever since. It can be exhausting to chase alert after alert, never really knowing which are false positives and which indicate real active adversaries in your environment. Something has to change – it is time to advance the practice of detection, to provide better and more actionable alerts. This requires thinking more broadly about detection, and starting to integrate the various different security monitoring systems in use today.
So it’s time to bring our recent research on detection and threat intelligence together within the context of Threat Detection Evolution. As always, we are thankful that some forward-looking organizations see value in licensing our content to educate their customers. AlienVault plans to license the resulting paper at the conclusion of the series, and we will build the content using our Totally Transparent Research methodology.
(Mostly) Useless Data
There is no lack of security data. All your devices stream data all the time. Network devices, security devices, servers, and endpoints all generate a ton of log data. Then you collect vulnerability data, configuration data, and possibly network flows or even network packets. You look for specific attacks with tools like intrusion detection devices and SIEM, which generate lots of alerts.
You probably have all this security data in a variety of places, with separate policies to generate alerts implemented within each monitoring tool. It’s hard enough to stay on top of a handful of consoles generating alerts, but when you get upwards of a dozen or more, getting a consistent view of your environment isn’t really feasible.
It’s not that all this data is useless. But it’s not really useful either. There is value in having the data, but you can’t really unlock its value without performing some level of integration, normalization, and analytics on the data. We have heard it said that finding attackers is like finding a needle in a stack of needles. It’s not a question of whether there is a needle there – you need to figure out which needle is the one poking you.
This amount of traffic and activity generates so much data that it is trivial for adversaries to hide in plain sight, obfuscating their malicious behavior in a morass of legitimate activity. You cannot really figure out what’s important until it’s too late. And it’s not getting easier – cloud computing and mobility promise to disrupt the traditional order of how technology is delivered and information is consumed by employees, customers, and business partners, so there will be more data and more activity to further complicate threat detection.
Minding the Store…
In the majority of our discussions with practitioners, sooner or later we get around to the challenge of finding skilled resources to implement the security program. It’s not a funding thing – companies are willing to invest, given the high profile of threats. The challenge is resource availability, and unfortunately there is no easy fix. The security industry is facing a large enough skills gap that there is no obvious answer.
Why can’t security practitioners be identified? What are the constraints on training more people to do security? It is actually pretty counter-intuitive, because security isn’t a typical job. It’s hard for a n00b to come in and be productive their first couple years. Even those with formal (read: academic) training in security disciplines need a couple years of operational experience before they start to become productive. And a particular mindset is required to handle a job where true success is a myth. It’s not a matter of whether an organization will be breached – it’s when, and that is hard for most people to deal with day after day.
Additionally, if your organization is not a Global 1000 company or major consulting firm, finding qualified staff is even harder because you have many of the same problems as a large enterprise, but far less budget and available skills to solve it.
Clearly what we are doing is insufficient to address the issue moving forward. So we need to look at the problem differently. It’s not a challenge that can be fixed by throwing people at it, because there aren’t enough people. It’s not a challenge that can be fixed by throwing products at it either, because organizations both large and small have been trying for years with poor results. Our industry needs to evolve its tactics to focus on doing the most important things more efficiently.
Efficiency and Integration
When you don’t have enough staff you need to make your existing staff far more efficient. That typically involves two different tactics:
- Minimize False Positives and Negatives: The thing that burns up more time than anything else is chasing alerts into ratholes and then finding out that they are out to be false positives. So making sure alerts represent real risk is the best efficiency increase you can manage. Obviously you also want to minimize false negatives because when you miss an attack you will spend a ton of time cleaning it up. Overall you need to focus on minimizing errors to get better utilization out of your limited staff.
- Automate: The other aspect of increasing efficiency is automation of non-strategic functions where possible. There isn’t a lot of value in making individual IPS rule changes based on reliable threat intel or vulnerability data. Once you can trust your automation, you can have your folks do tasks that aren’t suited to automation, like triaging possible attacks.
The other way to make better use of your staff is integration. The security business has grown incrementally to address specific problems. For example, when first connecting to the Internet you needed a firewall to provide access control for inbound connections. Soon enough your network was being attacked, so you deployed an IPS to address those attacks. Then you wanted to control employee web use, so you installed a web filter. Then you needed to see which devices where vulnerable and bought a vulnerability scanner, and so on and so forth.
This security sprawl continues in earnest today, with new advanced technologies to be deployed on the network, on endpoints, within your data center, and in the cloud. Of course you can’t turn off the old controls, so a smaller organization may need to manage 7-10 different security products and services. Larger organizations can have dozens. Obviously an integrated solution provides leverage by not having all those policies separated out, and providing a streamlined user experience for faster response.
The Goal: Risk-based Prioritization
To delve a bit into the land of motherhood and apple pie, organizations have been trying to allocate scarce resources based on potential impact to the organization. Yes, the mythical unicorn of security: prioritized alerts with context on what is actually at risk within your organization. There is no generic answer. What presents risk to one organization might not to another. What’s important to one organization clearly differs from others. Your threat detection approach needs to reflect these differences.
An evolved view of threat detection isn’t just about finding attacks. It’s about finding the attacks that present the biggest risk to your organization, and enabling an efficient and effective response. This involves integrating a bunch of existing security data sources (both internal and external) and monitors, then performing contextual analysis on that data to prioritization based on importance to your organization.
So how can you do that? We’re glad you asked – that is our subject for this series. First touching on data collection, and then the analytics necessary to detect threats accurately and efficiently. We will wrap up with a Quick Win scenario, which we use to describe tactics you can use right now to kick-start your efforts and build toward evolved threat detection.