SIEM Overview - Exabeam

What Is SIEM? Uses, Components, and Capabilities

Security information and event management (SIEM) solutions use rules and statistical correlations to turn log entries and events from security systems into actionable information. This information can help security teams detect threats in real time, manage incident response, perform forensic investigation on past security incidents, and prepare audits for compliance purposes.

The term SIEM was coined by Mark Nicolett and Amrit Williams, in Gartner’s SIEM report, Improve IT Security with Vulnerability Management. They proposed a new security information system on the basis of two previous generations. 

Security Information Management (SIM)
A first generation, built on top of traditional log collection and management systems. SIM introduced long-term storage, analysis, and reporting on log data, and combined logs with threat intelligence.

Security Event Management (SEM)
A second generation, addressing security events – aggregation, correlation and notification for events from security systems such as antivirus, firewalls and intrusion detection systems (IDS), as well as events reported directly by authentication, SNMP traps, servers, databases and others.

Modern SIEM security platforms combine SIM and SEM, aggregating both historical log data and real-time events and establish relationships that can help security staff identify anomalies, vulnerabilities and incidents.

The main focus of SIEM is on security-related incidents and events, such as succeeded or failed logins, malware activities or escalation of privileges. These insights can be sent as notifications or alerts, or discovered by security analysts using the SIEM platform’s visualization and dashboarding tools.

What is Next-gen SIEM?

SIEM is a mature technology and the next generation of SIEMs provide new capabilities:

  • User event behavior analytics (UEBA) in advanced SIEMs go beyond rules and correlations, leveraging AI and deep learning techniques to look at patterns of human behavior. This can help detect insider threats, targeted attacks, and fraud.
  • Security orchestration and automation response (SOAR) – Next-gen SIEMs integrate with enterprise systems and automate incident response. For example, the SIEM may detect an alert for ransomware and perform containment steps automatically on affected systems, before the attacker can encrypt the data.

New SIEM platforms provide additional advanced capabilities such as:

  • Complex threat identification – Correlation rules can’t capture many complex attacks, because they lack context, or can’t respond to new types of incidents. With automatic behavioral profiling, SIEMs can detect behavior that suggests a threat.
  • Detection without rules or signatures – Many threats facing your network can’t be captured with manually-defined rules or known attack signatures. SIEMs can use machine learning to detect incidents without pre-existing definitions.
  • Lateral movement – Attackers move through a network by using IP addresses, credentials and machines, in search of key assets. By analyzing data from across the network and multiple system resources, SIEMs can detect this lateral movement.
  • Entity behavior analysis – Critical assets on the network such as servers, medical equipment or machinery have unique behavioral patterns. SIEMs can learn these patterns and automatically discover anomalies that suggest a threat.
  • Automated incident response – Once a SIEM detects a certain type of security event, it can execute a pre-planned sequence of actions to contain and mitigate the incident. SIEMs are becoming full security orchestration and automation response (SOAR) tools.

Related content: Information Security

What Can a SIEM Help With?

Analyzes events and sends out alerts to notify security staff of immediate issues, either by email, other types of messaging, or via security dashboards.

Dashboards and Visualizations
Creates visualizations to allow staff to review event data, see patterns and identify activity that does not conform to standard patterns.

Automates the gathering of compliance data, producing reports that adapt to security, governance and auditing processes for standards like HIPAA, PCI/DSS, HITECH, SOX and GDPR.

Stores long-term historical data to enable analysis, tracking, and data for compliance requirements. Especially important in forensic investigations, which happen after the fact.

Threat Hunting
Allows security staff to run queries on SIEM data, filter and pivot the data, to proactively uncover threats or vulnerabilities.

Incident Response
Provides case management, collaboration and knowledge sharing around security incidents, allowing security teams to quickly synchronize on the essential data and respond to a threat.

SOC Automation
Integrates with other security solutions using APIs, and lets security staff define automated playbooks and workflows that should be executed in response to specific incidents.

How Does SIEM Work?

In the past, SIEMs required meticulous management at every stage of the data pipeline – data ingestion, policies, reviewing alerts and analyzing anomalies. Increasingly, SIEMs are getting smarter at pulling data together, from ever more organizational sources, and using AI techniques to understand what type of behavior constitutes a security incident.

Data Collection

Most SIEM systems collect data by deploying collection agents on end-user devices, servers, network equipment, or other security systems like firewalls and antivirus, or via protocols syslog forwarding, SNMP or WMI. Advanced SIEMs can integrate with cloud services to obtain log data about cloud-deployed infrastructure or SaaS applications, and can easily ingest other non-standard data sources.

Pre-processing may happen at edge collectors, with only some of the events and event data passed to centralized storage.

Data Storage

Traditionally, SIEMs relied on storage deployed in the data center, which made it difficult to store and manage large data volumes.

As a result, only some log data was retained. Next-generation SIEMs are built on top of modern data lake technology such as Amazon S3 or Hadoop, allowing nearly unlimited scalability of storage at low cost. This makes it possible to retain and analyze 100% of log data across even more platforms and systems.

Policies and Rules

The SIEM allows security staff to define profiles, specifying how enterprise systems behave under normal conditions.

They can then set rules and thresholds to define what type of anomaly is considered a security incident. Increasingly, SIEMs leverage machine learning and automated behavioral profiling to automatically detect anomalies, and dynamically define rules on the data, to discover security events that require investigation.

Data Consolidation and Correlation

The central purpose of a SIEM is to pull together all the data and allow correlation of logs and events across all organizational systems.

An error message on a server can be correlated with a connection blocked on a firewall, and a wrong password attempted on an enterprise portal. Multiple data points are combined into meaningful security events, and delivered to analysts by notifications or dashboards. Next-gen SIEMs are getting better and better at learning what is a “real” security event that warrants attention.

What are SIEMs Used For?

Security Monitoring

SIEMs help with real-time monitoring of organizational systems for security incidents.

A SIEM provides a unique perspective on security incidents, because it has access to multiple data sources – for example, it can combine alerts from an IDS with information from an antivirus product. It helps security teams identify security incidents that no individual security tool can see, and helps them focus on alerts from security tools that have special significance.

Advanced Threat Detection

SIEMs can help detect, mitigate and prevent advanced threats, including:

  • Malicious insiders – A SIEM can use browser forensics, network data, authentication and other data to identify insiders planning or carrying out an attack.
  • Data exfiltration (sensitive data illicitly transferred outside the organization) – A SIEM can pick up data transfers that are abnormal in their size, frequency or payload.
  • Outside entities, including advanced persistent threats (APTs) – A SIEM can detect early warning signals indicating that an outside entity is carrying out a focused attack or long-term campaign against the organization.

Forensics and Incident Response

SIEMs can help security analysts determine that a security incident is taking place, triage the event and define immediate steps for remediation.

Even if an incident is known to security staff, it takes time to collect data to fully understand the attack and stop it – the SIEM can automatically collect this data and significantly reduce response time. When security staff discover a historic breach or security incident that needs to be investigated, SIEMs provide rich forensic data to help uncover the kill chain, threat actors and mitigation.

Compliance reporting and auditing

SIEMs can help organizations prove to auditors and regulators that they have the proper safeguards in place and that security incidents are known and contained.

Many early adopters of SIEMs used it for this purpose – aggregating log data from across the organization and presenting it in audit-ready format. Modern SIEMs automatically provide the monitoring and reporting necessary to meet standards like HIPAA, PCI/DSS, SOX, FERPA and HITECH.

Introducing Exabeam Fusion SIEM

​​Exabeam Fusion SIEM is a cloud-delivered solution that combines SIEM with the world-class threat detection, investigation, and response (TDIR) of Extended Detection and Response (XDR). 

With powerful behavioral analytics built into Fusion SIEM, analysts can detect threats missed by other tools. Prescriptive workflows and pre-packaged content enable successful SOC outcomes and response automation. Fusion SIEM also provides the cloud-based log storage, rapid and guided search, and comprehensive compliance reporting expected of any modern SIEM.

With Fusion SIEM you can:

  • Leverage threat detection, investigation, and response
  • Collect, search and enhance data from anywhere
  • Detect threats missed by other tools through behavioral analytics
  • Achieve successful outcomes with prescriptive, threat-centric use case packages
  • Enhance productivity and reduce response times with automation
  • Meet regulatory compliance and audit requirements with ease

How Exabeam Fusion Works

Data from Anywhere Enhances Visibility 

Visibility is the first pillar of security operations, but it is a challenge to achieve as modern organizations are making data available everywhere. Inefficient and overly complex traditional logging tools often require knowledge of proprietary query language, and are slow to deliver results. The continuous spread of data, infrastructure and applications requires a new level of analytics for full visibility. Fusion SIEM collects data from the endpoint to the cloud, eliminating blind spots to give analysts a full picture of their environment. Rapid, guided search boosts productivity, and ensures analysts of all levels can access valuable data exactly when they need it.

Prescriptive TDIR Use Case Packages and Automation

It has become too complicated to build an effective SOC using legacy SIEMs and a selection of purpose-built security products. Every SOC is unique, with its own mix of tools, level of staffing and maturity, and processes and there is no standard way to tackle cyber security. Fusion SIEM solves this by leveraging prescriptive, threat-centered TDIR Use Case Packages that provide repeatable workflows and prepackaged content that spans the entire TDIR lifecycle. These use cases include all the content necessary to operationalize that use case, including: prescribed data sources, parsers, detection rules and models, investigation and response checklists, and automated playbooks.

Meet Regulatory Compliance and Audit Requirements 

Organizations must adhere to compliance regulations. Creating and maintaining compliance reports is time consuming but necessary. Whether you’re subject to GDPR, PCI, HIPAA, NYDFS, NERC, or utilizing a framework such as NIST, Fusion SIEM significantly reduces the operational overhead of compliance monitoring and reporting. Fusion SIEM’s pre-packaged reports provide huge time savings spent correlating information, solves the risk of missing vital data, and eliminates the need to manually create compliance reports through report builder tools.

See Exabeam in action: Request a demo

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Software: Basics, Next-Gen Features, and How to Choose

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See Our Additional Guides on Key Information Security Topics

Together with our content partners, we have authored in-depth guides on several other topics that can also be useful as you explore the world of information security

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This article defines a SOC and explains the difference between SOC teams and CSIRT teams. It also explains how SOCs operate, covers benefits and challenges of SOCs, and provides a guide for setting up your SOC.  

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Learn about MITRE ATT&CK, a security research project that is helping the security industry better understand techniques, tactics, and procedures (TTPs) used by threat actors, detecting them, and responding to them more effectively.

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This article defines a SOC and explains the difference between SOC teams and CSIRT teams. It also explains how SOCs operate, covers benefits and challenges of SOCs, and provides a guide for setting up your SOC.

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Information Security and Compliance

Learn about the intersection of information security and compliance in these additional articles by Exabeam’s content partners.