Why Managed Security Information and Event Management (SIEM) Is the Cornerstone of Modern Cyber Defense

Visibility is the foundation of effective cybersecurity. Without it, detecting and responding to malicious activity becomes a guessing game, leaving attackers free to exploit weaknesses unnoticed. Security tools such as firewalls and endpoint agents play a critical role, offering essential insights into network and host-level activity. However, these tools are often focused on specific areas and are limited in the broader context they can provide.

Security Information and Event Management (SIEM) solutions address these limitations by consolidating and analysing data from across an organisation’s entire infrastructure. This provides a more complete view of potential threats and attack patterns, connecting dots that would otherwise remain scattered. That being said, many traditional SIEMs struggle to deliver on this promise, often overwhelming security teams with unfiltered logs and irrelevant alerts. Instead of simplifying detection, they can bury critical insights in noise.

For smaller teams or organisations with limited resources, these challenges are amplified. Traditional SIEMs demand constant fine-tuning and highly skilled management to function effectively, making them a luxury only big enterprises can afford. This results in a tool that remains underutilised or shelved. Compounding the issue, the high costs tied to unpredictable data ingestion fees force organisations to choose between affordability and complete visibility.

This is where a Managed SIEM becomes indispensable. A properly managed SIEM solution compresses, filters, aggregates, and correlates telemetry data to cut through the noise, reduce costs, and provide security teams with clear, actionable insights. This enables faster detection, facilitates more precise responses, and empowers teams to proactively hunt threats before they escalate.

A Data Lake for Threat Hunting: Centralisation and Normalisation at Scale

One of the most powerful features of a SIEM solution is its ability to centralise and normalise vast quantities of log data.

Most devices—from servers and endpoints to firewalls and cloud services—produce logs that capture vital security-related activity. However, without centralisation, this data remains fragmented, inconsistent, and difficult to interpret in any meaningful way.

A SIEM brings all this information into one place and normalises the data into a consistent format. This makes it possible to apply detection rules, build correlations, and identify patterns that span multiple systems. This centralisation effectively creates a threat-hunting data lake: a unified environment where investigators can query, analyse, and cross-reference indicators. Unlike endpoint detection and response (EDR) tools, which primarily focus on host-level behaviour, a SIEM offers a much broader perspective across the entire infrastructure. This enables investigators to detect activity in areas that other tools simply don’t monitor, such as cloud logs, network appliances, or non-agent devices.

However, the full potential of a SIEM is unlocked when it is expertly managed. With carefully curated detections and the context provided by skilled management, a Managed SIEM can highlight anomalies, enrich events with threat intelligence, and surface high-risk behaviours. This reduces the operational burden on internal teams while enabling the proactive identification of early indicators of compromise, empowering organisations to respond before threats escalate.

Enhancing Visibility for Non-Agent Devices: The Value of Log Forwarding

Another often underappreciated advantage of SIEM is its ability to ingest data from systems where deploying an agent is either difficult or impossible. These include network appliances such as VPNs, firewalls, routers, switches, and legacy servers that cannot support agent installation.

These devices are often early targets for attackers. VPN gateways, for example, are commonly scanned for weak credentials or outdated firmware, while Remote Desktop Protocol (RDP) servers frequently face brute-force attacks. Since these systems are typically exposed to the internet and are relatively easy to exploit, they tend to be among hackers’ first targets when attacking an organisation.

While these devices may not support rich telemetry, nearly all of them support the forwarding of syslog, a protocol that computer systems use to send event data logs to a central location for storage. By forwarding these logs into a SIEM, organisations can monitor authentication attempts, configuration changes, and network anomalies in real time.

With the right parsing and alerting, a Managed SIEM transforms basic syslog data into high-value security insights. For instance, repeated failed login attempts from a single IP address targeting multiple accounts could indicate brute-force activity. Similarly, a sudden spike in VPN sessions from a region with no known users might suggest compromised credentials. Without a SIEM, these signals could easily be missed. With a SIEM, they become clear warnings. In many cases, forwarding logs from such devices can drastically improve an organisation’s visibility. It enables defenders to monitor areas that would otherwise remain blind spots and provides critical context for incident investigations.

Detecting and Disrupting Threats Early in the Attack Lifecycle

The earlier a threat is detected, the lower the cost and effort required to contain it. This principle lies at the core of the cyber kill chain, which outlines the stages of a typical intrusion. Catching an attacker in the early stages can prevent an incident from escalating into a breach.

A well-managed SIEM is uniquely positioned to achieve this. By collecting and analysing telemetry in near real time, it can detect malicious activity before attackers accomplish their objectives. Take brute-force attacks, for example. These are often used to compromise RDP or VPN services by automatically trying thousands of passwords. Such attacks are noisy, but they are only visible if someone is actively monitoring the relevant logs.

A Managed SIEM enables that monitoring. It can generate alerts for unusual login behaviour, excessive failed authentication attempts, or access attempts from suspicious locations. When integrated with other security tools, it can even automate response actions, such as blocking an IP address, disabling a user account, or terminating a VPN session.

Why Expert Management is Needed

Despite these many benefits, traditional SIEM solutions often fall short in practice. While they excel at consolidating and normalising vast amounts of telemetry, they demand constant fine-tuning and specialised expertise to remain effective. Without dedicated resources to manage configurations, tune alerts, and interpret insights, traditional SIEMs quickly become overwhelming.

This is where the value of a Managed SIEM becomes clear. Rather than placing the burden of deployment, configuration, tuning, and threat detection solely on internal teams, a Managed SIEM pairs the technology with experienced investigators who ensure it delivers real security outcomes.

For organisations without an in-house security operations centre (SOC), this model provides access to expert monitoring, tailored detections, and proactive guidance. This means organisations get not just more data but the right data, properly interpreted, enriched, and prioritised without having to build or maintain expensive in-house expertise.

A Powerful Tool in The Hunt for Hackers

In a world where cyber threats are increasing in both frequency and sophistication, the need for comprehensive visibility and rapid detection is more urgent than ever. A Managed SIEM offers both. It centralises data, extends monitoring to otherwise unmonitored devices, and helps defenders act before hackers can cause real harm.

Rather than seeing SIEM as a legacy tool or a compliance checkbox, we should recognise it as a critical pillar of modern cyber defence. With the right management and context, it becomes far more than a log aggregator. It becomes a proactive, intelligent engine for detecting and shutting down attacks, often before they even begin.

About the Authors

Anton Ovrutsky is the principal threat hunting and response analyst at Huntress. Ovrutsky transitioned into cybersecurity from a Service Desk role, initially gaining experience through governance, risk, and compliance work. He specializes in looking at the incidents that the SOC escalates that require more in-depth review. To put it another way, his expertise ensures that complex security incidents are thoroughly investigated and addressed. Anton holds several prestigious certifications, including CISSP, OSCP, OSCE, CCSP, and KCNA. Prior to joining Huntress, he gained valuable experience in the SIEM vendor SaaS space. Anton can be reached online at https://www.linkedin.com/in/antonovrutsky/?originalSubdomain=ca and at our company website https://www.huntress.com/.

Dray Agha is the senior manager, security operations centre at Huntress. Dray holds (among other certifications) an OSCP certification (Offensive Security Certified Professional). The training for OSCP covers several aspects of penetration testing, including network enumeration, vulnerability analysis, buffer overflows, web application attacks, privilege escalation and more. Dray specializes in Digital forensics and incident response and is interested in defensive and offensive information security. Dray can be reached online at https://www.linkedin.com/in/drayagha/?originalSubdomain=uk and at our company website https://www.huntress.com/.