1. Start by Correlating Alerts To Triage
An analyst, whether a real person or a hypothetical superpowered nonhuman agent, needs to look at incidents, not individual alerts. It’s truly rare that a single alert is worthy of action. Most of the time, it’s a combination of things, such as a strange sign-on, an impossible geolocation for a user, an anomalous process on a desktop, a business process rule change or a pile of data moving in the wrong direction. Individually, these are interesting but unworthy of action in the sea of daily alerts. However, when these alerts are tied to the same identity, to the same time window and to high-value systems, that’s important.
Correlating alerts means looking at multiple factors, such as identity, asset, time window and session, geolocation, known indicators of compromise and velocity. Everything must be gathered, deduplicated (because networks always duplicate alerts) and then turned into an incident that can be triaged.
Correlation doesn’t mean getting rid of raw alert data; it means compiling small pieces and turning them into big pieces before handing them to an analyst. The goal is to give the analyst all of the information they need to decide whether something is important — not just alerts but also contextual information, such as risk profile and recent configuration changes.
2. Score Risk Rigorously for Every Incident
Cybersecurity vendors typically try to help with this process by assigning a risk score to common vulnerabilities and exposures, and such CVE severities are nice inputs to have. But the real prioritization has to be from a small business’s own risk scoring model. That means knowing a lot about the applications and servers involved. Which are for production, and which are for testing? Which are critical, and which are not? Which are exposed to the internet or have weak internal access controls? Which have sensitive data or are subject to regulatory controls? Which identities are highly privileged, and which are tightly constrained?
These factors, among others, are inputs to the prioritization process. Security professionals should also include external information, such as the CVE severity and whether there’s active exploitation being observed elsewhere, along with information that is relevant to the incident, such as the scope of the alerts or whether lateral movement is being detected.
All of this helps an IT team member decide what they need to look at and how much containment or reaction is required. IT leaders shouldn’t think they can make a risk scoring model right the first time. Transparency in risk scoring is important. Analysts need to be able to override priorities, and they’ll be able to do so with greater confidence when they understand why something showed up in their action queue. Their feedback on the accuracy and relevance of incidents is critical to improving the model.
Click the banner below to find the right IT support for your small business.
