Security Information and Event Management (SIEM) 

What is SIEM, and how does it work?

SIEM Definition

Security information and event management (SIEM) tools centralize, correlate, and analyze data across the IT network to detect security issues. Core functionality of a SIEM includes log management and centralization, security event detection and reporting, and search capabilities. This combination helps companies meet compliance needs and identify and contain attackers faster.

What is a SIEM, and how does it work?

A modern SIEM needs three core capabilities—data collection, analytics, and response—to provide the security monitoring and visibility needed in today’s hybrid and multi-cloud environments. A SIEM’s job is to ingest data across your entire network (data collection), identify malicious behavior (analytics), and provide alerts to security and IT teams to give them the visibility and information to respond before the issue becomes serious (response). If compliance reporting is an important driver, a SIEM should also be able to assist with dashboards and ensuring security policy is being enforced.

The benefits of a SIEM

When deployed properly, a SIEM offers organizations the visibility they need to measurably reduce risk across the entire network to detect both known and unknown threats. SIEM solutions have been around for the better part of two decades, and today’s modern SIEMs don’t quite resemble their original, log management counterparts. As the security landscape has evolved, SIEMs have evolved as well (at least, some of them have). The most effective, automated solutions today include:

  • Fewer false positives
  • Accurate malware detection
  • Comprehensive analysis of all infrastructure
  • Ability to learn new threats
  • Endpoint detection

What to look for in a SIEM solution

Time and accuracy matter here. With a SIEM tool, your company may see billions of events each day, and that's a lot of information to sift through. You need a SIEM solution that can verify what needs follow-up and, just as important, what's harmless behavior. The more adaptive your solutions can be, the better the chances you won't have a public relations nightmare or financial crisis on your hands. 

Here's a short checklist of what to look for in a SIEM solution:

Setting up a SIEM tool

Setting up SIEM tools is a complex task for even the most advanced security practitioner, but when done correctly, it can eliminate blind spots across your network. The first step consists of understanding your existing network and security stack and figuring out how to collect log information from those points. You’ll also need to consider planning for hardware if a software as a service (SaaS) storage option isn’t offered by the vendor. Finally, an ongoing step is to write rules to detect events of interest and create reports to highlight key metrics on overall network risk. For third-party analysis of SIEM tool features and vendors, check out the 2018 Gartner Magic Quadrant for SIEM.

Managing logs in a SIEM to ensure security and meet compliance

Managing logs effectively with your SIEM tool is essential for network visibility, compliance, and reliable incident detection and response. You as a security practitioner need the ability to ask questions of your data (usually using structured query language or SQL) to identify Indicators of Compromise (IoCs), find the users and systems affected, and share the final scope with remediation teams. Managing logs usually involves indexing data and correlating it with other data sets. The end goal is to give you an easy way to search for threats from one unified dashboard.

Alerts and reporting with your SIEM tool

After general setup, configuring your alerts and reports is key to being efficient with your SIEM. As a security practitioner, you’ll need to constantly refine your SIEM to provide you with the important security events happening on your network. A common problem with SIEM tools is that they produce too many un-prioritized alerts, more than the security team can take the time to investigate. That’s why it’s important to continuously tune new and existing rules to effectively find only the relevant threat actions.

It's a lot to remember, and a lot to take in. But feeling overwhelmed can't stop you from taking action. Attacks come in all shapes and sizes, and understanding their full scope is not just something that's “nice to have.” When you use incident and detection response effectively, you start your company on a path to streamlining more tasks through a better understanding of what policies are working and which ones might need some work, both now and in the future.