XDR vs SIEM: Current Capabilities and How They Will Evolve

XDR vs SIEM: Current Capabilities and How They Will Evolve

What is XDR?

EXtended Detection and Response (XDR) services provide threat detection, investigation, and response (TDIR) capabilities. XDR services offer correlated input coverage against a variety of threats from disparate security tools in the stack with a fast time-to-value. To perform efficiently and maximize human capital, XDR services employ advanced analytics and automation.

XDR solutions are cloud-ready and tend to be cloud-delivered. XDR vendors offer coverage for various threat-centric scenarios, ranging from simple hacker tool attacks against web servers to sophisticated combination threats such as Ransomware and lateral movement through data exfiltration. XDR solutions are designed to accommodate heterogeneous environments and enable immediate time-to-value as a turnkey solution.

What is SIEM?

Security information and event management (SIEM) solutions use security information management (SIM) function and capabilities in combination with security event management (SEM) functionalities and centralize these into one platform.

SIEM platforms deploy collection agents across an IT ecosystem and/or aggregate security-related log and alert events from multiple locations, including end-user devices, network monitoring devices, servers system logs, as well as security devices such as perimeter load balancers and firewalls, intrusion prevention/detection systems (IPS/IDS), web access firewalls (WAF), and antivirus.

Collection agents are tasked with forwarding events to a central data repository, sorting events by labeled severity and/or timestamp to be reviewed through a centralized management console. SIEMs allow security analysts to see events and alerts as they are delivered and explore this data for incidents.

In addition, SIEMs often provide compliance reporting capabilities for mandates such as PCI, SOX, HIPAA, and GDPR.

What are the Capabilities of XDR?

Threat Detection

The XDR solution analyzes both traffic passing through the data center (known as East-West traffic) and data flowing between the data center and other networks (known as North-South traffic). 

It can improve intrusion detection, but it also supports a zero-trust security model by identifying threats that already exist in your network. XDR combines event data with threat intelligence and uses behavioral analytics to identify suspicious or anomalous activity in the environment, including zero-day threats.

Incident Response

XDR solutions provide a range of tools to help security teams respond to threats detected in their environment. Alerts are prioritized and aggregated into attack cases, allowing security analysts to see the full background of an attack without further forensic analysis.

The XDR solution provides a single, central user interface for incident investigation and attack response. It also supports security orchestration, allowing security teams to respond to attacks from the same interface they use to monitor and triage threats.

Micro Segmentation

XDR solutions offer micro-segmentation capabilities at the workload, application, and user level. This enables consistent implementation of security policies and access controls across bare metal and multi-cloud data centers, reducing the attack surface and preventing lateral movement.

Control Over Endpoints

Process whitelisting and blacklisting improves control over endpoint behavior, by allowing only known good processes. This makes it possible to lock down high risk environments, such as fixed function or IoT devices. 

Improved Productivity

Security teams are overwhelmed by alerts that lack information and context, and when they discover a meaningful alert, must investigate and respond to it using multiple different tools. XDR increases operational efficiency by using AI to automatically piece together attack timelines, reducing time to triage, identify and investigate relevant incidents. It also provides one integrated platform for investigating and responding to alerts. 

Efficiency and Scalability

XDR solutions are delivered as an integrated platform that can be deployed rapidly and deliver value quickly. They are typically cloud-based and can be scaled up dynamically based on an organization’s data needs.

Related content: XDR Solutions

What are the Capabilities of Traditional SIEM?

SIEM solutions have been on the market for over two decades, and have been refined from monitoring only firewall and intrusion detection sensors to cloud and network security products of all kinds. Here are the traditional core features of a SIEM platform:

Log Management

SIEM solutions collect logs from multiple IT systems and combine them into a standardized, centrally-stored dataset which can be queried by security teams and used to generate automatic alerts.

Event Correlation

SIEM analyzes log data and uses correlation rules and statistical analysis to identify possible security incidents. For example, a SIEM can identify a failed login attempt by the same user across multiple endpoints, servers, and cloud services.

Threat Intelligence

SIEM integrates with threat intelligence feeds that enrich security events with additional context, such as the identity of the attacker, blacklisted IP address sources, or known attack patterns.

Security Alerts

a SIEM sends alerts to security teams, either through the SIEM interface or pushed to various notification channels. Alerts provide detailed information about the event and enable analysts to triage and investigate the incident further.

Data Exploration

SIEM stores event data which allows skilled security analysts to search and explore security data over a period of time, often using SQL queries, as part of incident investigation or proactive threat hunting.

Compliance Reporting

SIEMS are positioned as a centralized hub within the larger security infrastructure, the SIEM often supports packaged reporting for compliance mandates such as PCI DSS, SOX, GDPR, and HIPAA.

What are the Challenges of Traditional SIEM?

The primary challenge with traditional SIEM is alert fatigue — a SIEM generates a large number of alerts, some of which are false positives, placing a large burden on security teams to triage and investigate every alert. Some SIEM or security engineers attempt to do this through elaborate tuning of firewall and IDS (or other “noisy” tool) outputs to lower the impact on the SIEM, both to reduce alert fatigue and to potentially save money on log storage and processing.

Next-gen SIEMs aim to solve this by introducing advanced analytics based on machine learning.

What are the Capabilities of Next-gen SIEM?

In 2019, Gartner introduced the vision of a next-generation SIEM that includes additional capabilities, most importantly machine learning–based analysis and response automation. Since then, next-generation SIEM solutions have been introduced offering all the basic SIEM capabilities, and some of the following:

User and Entity Behavior Analytics (UEBA)

Next-gen SIEM provides UEBA technology, which creates behavioral profiles of users, groups, machines, and applications in the environment, and identifies anomalies that could indicate a security incident.

Security Orchestration and Automation Response (SOAR)

Next-gen SIEMs provide orchestration capabilities, which allow them to integrate with IT and security tools and control multi-step processes spanning multiple systems. They also enable incident detection, investigation and response automation using security playbooks, allowing the SIEM to respond autonomously to security incidents and breaches.

Collecting Data from Additional Sources

Modern IT environments span beyond the traditional network perimeter. Next-gen SIEM can collect data from cloud services, BYOD and IoT devices, and other new data sources.

Scalable Data Storage

Next-gen SIEMs use data lake technology to store much larger volumes of data at lower cost. This enables longer retention of larger volumes of security data.


next-gen SIEMs like Exabeam Fusion SIEM include XDR within the suite of applications and capabilities for improved event context, analytics, and TDIR use cases.

A next-gen SIEM can improve security operations by:

  • Leveraging UEBA to reduce false positives
  • Matching indicators of compromise (IoC) to a particular type of threat, reducing the time to respond (TTR) and time to investigate (TTI) for events
  • Aggregating multiple events into one attack timeline
  • Reduce time to action through automating responses

Weighing SIEM vs XDR

SIEM and XDR have technical similarities, but serve different purposes. 

Here are some of the key differences between next-gen SIEMs and XDR:

  • Functional coverage – SIEM provides several functionalities including threat detection, compliance, storage, and reporting. XDR focuses on one functionality: threat detection, investigation and response (TDIR).
  • Customization – SIEM enables unlimited customization for edge cases, while XDR is mainly designed for effective TDIR.
  • Data storage – SIEM acts as a central data store for the security organization, supporting long-term storage, while XDR typically accesses data from other sources and stores it temporarily for analysis. 
  • Delivery model – SIEM can be on-premises or cloud-based, while XDR is primarily cloud delivered.
  • Automation – SIEM can offer highly customizable orchestration and automation using both security playbooks and other IT playbooks. XDR provides pre-packaged playbooks for specific TDIR use cases.
  • Market positioning – next-gen SIEM is replacing traditional SIEM and security data lakes. XDR typically augments legacy SIEM and data lakes.

Related content: XDR Solutions

Choosing Your Investment: Next-gen SIEM vs XDR

When Should You Use Next-gen SIEM?

Next-gen SIEMs are most suitable for:

  • Identifying unknown threats, including new attack patterns and insider threats
  • Enabling customizable data exploration
  • Centralized data store and log retention for growing security data in the modern IT environment
  • Highly customizable response automation and orchestration
  • The same compliance and reporting use cases as traditional SIEM

When Should You Use XDR?

XDR is most suitable for:

  • An existing SIEM investment is already in place, and the team is looking to enhance the capabilities of the analysts to improve TTR and TTI
  • Identifying known and unknown threats and immediately assigning to threat categories
  • Rapid and effective TDIR using prepackaged content for common threat use cases
  • Supporting manual and automated response to critical threats
  • Improving security analyst productivity and reducing response time

Next-Gen Fusion SIEM and Fusion XDR with Exabeam

Exabeam Fusion XDR is a cloud-delivered solution that takes an outcome-based approach and offers prescriptive workflows and pre-packaged, threat-specific content to efficiently solve threat detection, investigation, and response (TDIR). It has pre-made integrations with hundreds of 3rd-party security tools and Exabeam’s market-leading behavior analytics combine weak signals from multiple products to find complex threats missed by other tools. Automation of triage, investigation, and response activities turbocharges analyst productivity and reduces response times.

Exabeam Fusion SIEM is a cloud-delivered next-gen SIEM that provides our industry-leading Fusion XDR for threat detection, investigation, and response embedded into the full suite of next-gen SIEM offering, including cloud-based log storage, search, and compliance reporting.

See Exabeam in action: Request a demo