SIEM vs XDR 2025: Which Solution to Choose for Your Company? - Comprehensive Comparison
Introduction: The Data Trap, or Why More Doesn't Mean Better
Imagine you are the captain of a ship on a rough sea. Water is everywhere—infinite amounts of it. But as your supplies run low, you realize a cruel irony: you are drowning in water, yet dying of thirst.
For over two decades, cybersecurity professionals have found themselves in a similar predicament. We believed that if we gathered all logs from every device in our network into one place, we would be safe. We built massive systems that swallowed terabytes of data daily, but instead of knowledge, we gained noise. We were drowning in data, yet starving for true insight.
The traditional approach, with the SIEM (Security Information and Event Management) system at its heart, has hit a wall. Its "collect everything and sort it out later" philosophy proved ineffective against modern, dynamic attacks. This is precisely why a new concept is taking the stage: XDR (Extended Detection and Response).
This isn't just another name for the same product. It is a fundamental shift in thinking, where what matters is not the quantity of data, but its quality and context.
In this article, we will uncover several surprising truths about this technological revolution. We will show why what you knew about digital defense might already be outdated and how the rules of the game are changing in the fight for security in the digital world.
1. Surprise #1: It’s Not About the Logs, It’s About the Story They Tell
For years, SOC (Security Operations Center) specialists were like archivists, meticulously cataloging individual facts—logs. However, the transition from SIEM to XDR is a career change from archivist to detective. A detective doesn't collect random footprints; they look for connections, motives, and build a coherent story of the crime.
This is exactly what XDR does, but its raw material is not logs, but something far richer—telemetry. The fundamental difference between these two data sources is key:
- Log (SIEM): A discrete, single record of what happened. For example: "User John Smith logged into server X at 10:00 AM." It is a single, passively generated fact.
- Telemetry (XDR): A continuous, active stream of contextual data about how it is happening. It records system calls, process creation, network traffic, and memory modifications. It is a full narrative, not a single sentence.
This difference is best illustrated by a "Living off the Land" attack, where attackers use legitimate system tools (like PowerShell) for malicious purposes.
A traditional SIEM will see a series of seemingly innocent events: PowerShell launch, connection to an IP address, file modification. Each of these events alone is not alarming.
XDR, on the other hand, thanks to telemetry collected directly from the system kernel, sees the whole history: a process that dumped the memory of the LSASS process (a critical Windows element managing user credentials), then established an unusual network connection, and finally attempted to inject code into another legitimate process.
XDR does not see isolated facts, but the entire chain of cause and effect, creating a coherent and unambiguously malicious story. This fundamental shift in data quality also has deep financial implications that often remain hidden at first glance.
2. Surprise #2: The True Cost of Security Lies in People, Not Licenses
When analyzing the costs of security tools, most managers focus on the license price. This is a mistake that leads to expensive errors. The true cost of a system is revealed by the Total Cost of Ownership (TCO), which includes not only licenses but also infrastructure, implementation, and—most importantly—the human resources needed to operate it.
Traditional SIEM is synonymous with high, hidden human costs. To function correctly, it requires an army of highly skilled and expensive engineers. Their tasks include:
- Writing and maintaining parsers: Every new data source, every software update from a vendor can change the log format, forcing engineers to tediously rewrite code that translates data into a language the SIEM understands.
- Constant rule "tuning": To avoid a flood of false alarms, analysts must constantly modify and create new correlation rules. This is a reactive, time-consuming, and error-prone process.
This human factor is so significant that market reports consistently indicate that personnel costs can make up the overwhelming majority of a SIEM system's Total Cost of Ownership.
The XDR economic model approaches this problem from a completely different angle. Instead of burdening people, it bets on automation. Because telemetry data is structured at the source, the need to write parsers disappears. Built-in, machine learning-based detection models eliminate the need to manually create thousands of rules.
As Forrester reports, next-generation platforms can reduce false positives by up to 79%, directly freeing up analyst time.
As a result, although the initial cost of an XDR license might seem higher, it often offers a much faster Return on Investment (ROI). It optimizes the most valuable and expensive resource in every security team: the time and expertise of experts. Choosing between SIEM and XDR is therefore not just a matter of cost, but a fundamental strategic decision.
3. Surprise #3: It’s Not a Fight to the Death. It’s a Forced Marriage of Convenience.
In the tech market, the clash between SIEM and XDR is often portrayed as a fight to the death where there can be only one winner. However, for mature, large organizations, this is a false dichotomy. The truth is that in many cases, both technologies are not rivals, but partners in a forced, yet very effective, marriage of convenience.
Each of these platforms has its own kingdom where it remains indispensable:
- SIEM is the undisputed king of compliance and historical analysis. When an auditor asks for logs from five years ago or a regulator requires detailed data access reports, SIEM is the only tool that can meet these requirements. Its strength is long-term archiving and the ability to search vast historical data sets.
- XDR is the master of real-time detection and rapid response. When an advanced attack, such as ransomware, attempts to encrypt data, XDR dominates thanks to its speed, precision, and built-in automated response capabilities.
The most effective strategy proves to be a hybrid model (SIEM + XDR). In this architecture, roles are clearly divided:
- XDR acts as the "first line of defense" and rapid response system. It detects and neutralizes 80-90% of tactical threats, sending only confirmed, high-quality alerts to the SIEM.
- SIEM acts as a strategic "archive" and "system of record." It stores data for audit purposes, analyzes long-term trends, and collects logs from sources that XDR does not cover, such as industrial systems (OT).
This collaboration allows for reduced SIEM licensing costs (since less data is sent to it), while gaining the speed and effectiveness of XDR. And this intelligent partnership is made possible by new standards that finally solve the age-old problem of communication between tools.
4. A Look into the Future: The End of the "Tower of Babel" and the Rise of AI Assistants
Historically, one of the biggest brakes on cybersecurity development was the lack of a common language. Every vendor created logs in their own unique format, forcing organizations to build a sort of "Tower of Babel" and hire translators—engineers writing parsers. This "parser hell" generated enormous costs and slowed down innovation.
Fortunately, this era is coming to an end thanks to a revolutionary initiative: the Open Cybersecurity Schema Framework (OCSF). Backed by industry giants like AWS, Splunk, and CrowdStrike, OCSF is an open standard that creates a common language for all security tools. In practice, this means data from a firewall, EDR system, and cloud platform can be instantly understood and correlated without the need for "translation."
However, the benefits go beyond eliminating parsers. OCSF introduces the concept of Detection Portability. This means that detection rules, written in universal formats like Sigma, can be moved between different tools without having to be rewritten. This is a strategic shift that protects investments in analytics and significantly reduces vendor lock-in.
This standardization opens the door for a new wave of innovation, spearheaded by Generative Artificial Intelligence (GenAI).
The first AI assistants, known as Security Copilots, are already appearing in security operations centers, fundamentally changing the work of analysts. Instead of writing complex queries in specialized languages, an analyst can ask a question in natural language, e.g., "Show me all computers that connected to this suspicious IP address and had a PowerShell process running."
AI will not only provide the answer but also generate an incident summary in business language, understandable to the board. We stand on the threshold of a new era where communication barriers between tools disappear, and artificial intelligence becomes a powerful ally of humans in the defense against cyber threats.
Need Help Choosing SIEM or XDR?
If you're wondering which solution best fits your organization's needs, want to optimize your existing SOC, or implement a hybrid model combining SIEM and XDR – contact us. We'll help you choose the optimal solution tailored to your budget, infrastructure, and security objectives.
What we offer
- SIEM vs XDR strategic consulting - needs analysis and optimal solution recommendation
- Existing SOC audit - evaluation of current tools and processes effectiveness
- Detection platform implementation - SIEM, XDR, or hybrid model deployment
- False Positive Rate optimization - rule tuning and false alarm reduction
- Analyst training - preparing SOC teams to work with new tools
- SOAR integration - response automation and security tool orchestration
See Also - Related Topics
SOC Technology Articles
- Security Operations Center (SOC): Comprehensive Guide for 2026 - How to build a modern security operations center using SIEM, XDR, and SOAR
- SOAR - Security Operations Automation - How SOAR orchestrates SIEM and XDR, automating threat response
- Threat Hunting - Advanced Guide - Proactive threat hunting using XDR telemetry
IT Security Management
- Managed Security Services Provider (MSSP) - Selection Guide - SOC outsourcing: how to choose a provider offering SIEM/XDR as a Service
- Cloud Security - Securing Infrastructure in the Cloud - SIEM and XDR in AWS, Azure, GCP environments
- Incident Response Plan - How to Prepare a Company for a Cyberattack? - How SIEM and XDR support rapid incident response per NIS2
FAQ - Frequently Asked Questions about SIEM and XDR
What's the difference between SIEM and XDR?
SIEM (Security Information and Event Management) is a security event management system that aggregates logs (discrete event records) from all sources in the infrastructure, correlates them according to defined rules, and generates alerts. SIEM excels at compliance, historical analysis, and long-term data retention. XDR (Extended Detection and Response) is an integrated detection and response platform that collects telemetry (continuous stream of contextual data) from sensors on endpoints, network, cloud, and identity systems. XDR uses machine learning for automatic correlation and offers native rapid response capabilities (isolation, blocking). Main difference: logs vs telemetry, compliance vs real-time detection, manual rules vs AI/ML.
Does XDR replace SIEM?
Not entirely. XDR excellently replaces SIEM in real-time threat detection and rapid response, offering much better precision (lower False Positive Rate) and automation. However, SIEM remains irreplaceable in three areas: (1) Compliance and audits - regulations (NIS2, GDPR, PCI-DSS) often require long-term log retention that XDR doesn't offer, (2) Historical analysis - SIEM allows searching data from months/years ago, (3) Wide source range - SIEM collects logs from OT systems, legacy, business applications that XDR doesn't cover. That's why mature organizations favor a hybrid model (SIEM + XDR), where XDR detects 80-90% of threats while SIEM serves as archive and compliance system.
How much does SIEM vs XDR implementation cost?
Total Cost of Ownership (TCO) differs significantly between solutions. SIEM: License $100-500k/year (volume-dependent), infrastructure (servers, storage) additional $50-200k, but the biggest cost is personnel - 3-5 engineers for writing parsers, rules, tuning the system ($300-500k/year personnel costs). XDR: License $50-300k/year (often cheaper with per-endpoint pricing), minimal infrastructure (SaaS platform), personnel costs significantly lower (1-2 analysts) thanks to automation and lower False Positive Rate (saving $200-300k/year). Conclusion: XDR has higher license cost but significantly lower TCO due to personnel cost reduction. Hybrid model optimizes both - less data in SIEM (lower costs) + faster detection via XDR.
What's the False Positive Rate in SIEM vs XDR?
False Positive Rate (false alarm indicator) is a key metric affecting SOC effectiveness. SIEM generates high FPR: 30-50% of alerts are false alarms because it relies on static correlation rules that are difficult to tune to dynamically changing environments. Analysts waste 32 minutes on average verifying one false alert, leading to alert fatigue and burnout. XDR achieves significantly lower FPR: 5-15% thanks to machine learning, behavioral analysis, and multi-source telemetry correlation (endpoint + network + cloud + identity). Forrester reports indicate that next-gen XDR platforms can reduce false alarms by 79% compared to traditional SIEM, directly translating to analyst productivity and faster detection of real threats.
What is telemetry and how does it differ from logs?
Log is a discrete, single event record - e.g., "User John logged in at 10:00". It's a passively generated fact without context. Telemetry is a continuous, active stream of detailed contextual data about how something is happening - it records system calls, process creation, network connections, RAM changes, file access. Example difference: Living off the Land attack (using legitimate tools like PowerShell for malicious purposes). SIEM sees a series of seemingly innocent logs: PowerShell launch, IP connection, file modification. XDR, thanks to telemetry, sees the full story: process dumped LSASS memory (credential theft), established unusual connection, injected code into legitimate process - a coherent and unambiguously malicious narrative. Telemetry = deep context, logs = single facts without context.
Can I use SIEM and XDR simultaneously?
Yes, and it's the best strategy for most organizations. Hybrid model (SIEM + XDR) combines advantages of both platforms: XDR acts as "first line of defense" - detects 80-90% of tactical threats in real-time, automatically responds (endpoint isolation, blocking), sends only confirmed, high-quality alerts to SIEM (not raw logs). SIEM serves as strategic "archive and system of record" - stores data for audit purposes (NIS2, GDPR require 5-10 year log retention), analyzes long-term trends, collects logs from sources XDR doesn't cover (OT systems, legacy, business applications). Benefits: Reduction of SIEM license costs (less data ingested), elimination of alert fatigue (XDR filters noise), faster detection + compliance. Companies like banks, telcos, healthcare use this model as standard.
How does XDR detect Living off the Land (LotL) attacks?
Living off the Land (LotL) attacks use legitimate system tools (PowerShell, WMI, PsExec, certutil) for malicious purposes, making them invisible to traditional signature-based detection systems. SIEM struggles greatly with detecting LotL because it sees individual logs: "PowerShell.exe launched" (normal), "IP connection" (normal), "File modified" (normal). Each event separately doesn't raise suspicion. XDR excellently detects LotL thanks to behavioral telemetry at kernel level: it records the full cause-and-effect chain - PowerShell process dumped LSASS process memory (critical Windows component managing credentials), then established unusual network connection to address outside the company, and finally attempted code injection (CreateRemoteThread) into legitimate explorer.exe process. XDR sees the entire attack narrative, not isolated facts, and correlates it with TTP (Tactics, Techniques, Procedures) database known from MITRE ATT&CK framework.
What is the SIEM+XDR hybrid model and who is it suitable for?
Hybrid model is an architecture where XDR and SIEM collaborate, dividing tasks according to strengths. Role division: XDR serves as operational detection system - monitors endpoints/network/cloud in real-time, detects threats using AI/ML, automatically responds (isolation, blocking), sends only enriched, confirmed high-severity alerts to SIEM (not raw logs). SIEM acts as long-term archive and compliance system - stores all logs for years (regulatory requirements), analyzes historical trends, collects data from systems outside XDR scope (OT, legacy), generates audit reports. Benefits: SIEM cost reduction (80-90% less data ingested), alert fatigue elimination (XDR filters false alarms), faster detection + compliance maintenance. For whom: Medium and large organizations with regulatory requirements (banks, telcos, energy, healthcare) that need both fast detection and long-term data retention.
What are the key success metrics for SIEM and XDR?
MTTD (Mean Time to Detect) - average time to detect threat. SIEM: typically hours (requires manual correlation and verification), XDR: minutes (automatic AI correlation). MTTR (Mean Time to Respond) - average reaction and neutralization time. SIEM: hours/days (requires manual analyst response), XDR: minutes/seconds (automatic endpoint isolation, IP blocking). False Positive Rate - percentage of false alarms. SIEM: 30-50%, XDR: 5-15%. Dwell Time - time intruder spends in network unnoticed. Goal: reduction from days/weeks to hours. Incident Closure Rate - percentage of incidents fully closed within specified time. 1-10-60 Rule (industry benchmark): 1 minute to detect, 10 minutes to investigate, 60 minutes to remediate (isolate and remove threat). XDR achieves these goals, traditional SIEM - doesn't.
How does OCSF (Open Cybersecurity Schema Framework) change the SIEM/XDR market?
OCSF (Open Cybersecurity Schema Framework) is a revolutionary open standard supported by industry giants (AWS, Splunk, CrowdStrike, Palo Alto Networks) that creates a common language for all security tools. Solves SIEM's biggest problem: "parser hell" - each vendor created logs in their own unique format, forcing organizations to hire armies of engineers writing parsers (translating data into SIEM-understandable language). With OCSF: data from firewall, EDR, cloud platform are natively standardized and can be immediately correlated without parsers. Benefits: (1) Elimination of parser engineering costs (saving hundreds of thousands USD/year), (2) Detection Portability - detection rules written in universal formats (Sigma) can be moved between different SIEM/XDR without rewriting, (3) Vendor lock-in reduction - easier vendor switching. OCSF opens doors for AI - data standardization enables faster machine learning model training and generative AI (Security Copilots).
Do small and medium-sized companies need SIEM or XDR?
Every company needs threat detection, but tool choice depends on size, budget, and regulatory requirements. Small companies (<50 employees): XDR in MDR (Managed Detection and Response) model - full outsourcing to MSSP, cost $2-5k/month, no need for own SOC. Alternative: EDR + managed service. SIEM usually too expensive and complex. Medium companies (50-500 employees): XDR SaaS or co-managed model (XDR + 1-2 internal Tier 2/3 analysts + Tier 1 outsourcing to MSSP). SIEM only if compliance requires (PCI-DSS, NIS2). Large companies (500+ employees): Hybrid SIEM+XDR model with own 24/7 SOC or hybrid (internal Tier 2/3 + external Tier 1). Conclusion: XDR has lower entry barrier (cost, complexity) than SIEM, making it better choice for smaller organizations.
What's the future of SIEM and XDR in the AI era?
The future is Autonomous SOC powered by Generative AI and agentic automation. SIEM evolves toward AI-powered analytics platform - instead of manually writing correlation rules, analysts use Security Copilots (AI assistants) who answer questions in natural language ("Show computers that connected to this suspicious IP and had PowerShell running"), generate reports for management, automatically create SOAR playbooks. XDR becomes autonomous platform - intelligent AI agents independently conduct investigations, correlate telemetry in real-time, detect advanced behavioral anomalies (zero-day attacks), autonomously isolate threats without human intervention (Human-in-the-loop only for critical decisions). Human role changes from "console operator" to strategic Threat Hunter - proactive hunting for most advanced APT threats, managing AI algorithms, making decisions in ethically ambiguous situations, communicating with business.
Conclusion: From Log Guardian to Digital Hunter
The revolution in cybersecurity has already happened. Old paradigms, based on hoarding every piece of information in the hope of finding a needle in a haystack, are fading into the past. We have realized that more does not mean better, and true strength lies in the quality of data, not its quantity. We have redefined costs, recognizing that the most valuable resource is people, not licenses. Instead of a technology war, we have chosen intelligent synergy, where SIEM and XDR complement each other. And the future, driven by open standards and artificial intelligence, promises even greater automation and efficiency.
However, a key question remains: what will be the role of the human in this new, increasingly automated world?
The evolution of tools creates a unique opportunity. Perhaps analysts will finally be able to stop being "console operators" and "log guardians," and become who they were always meant to be—creative strategists, analysts, and true "threat hunters," focused on tracking down the most advanced adversaries.
Aleksander
Sources
XDR vs. SIEM: 4 Key Differences, Pros/Cons, and How to Choose - Cynet What is the Difference Between XDR vs. SIEM? - Palo Alto Networks From Data Chaos to Cohesion: How OCSF is Optimizing Cyber Threat Detection XDR vs SIEM: How These Solutions Compare for Threat Detection
About the Author

Dyrektor ds. Technologii w SecurHub.pl
Doktorant z zakresu neuronauki poznawczej. Psycholog i ekspert IT specjalizujący się w cyberbezpieczeństwie.
Powiązane artykuły

Security Operations Center (SOC): Kompleksowy Przewodnik na 2026 | Budowa i Wdrożenie
Poznaj wszystko o Security Operations Center (SOC) - od budowy zespołu, przez technologie SIEM/XDR/SOAR, wymogi NIS2, modele wdrożenia, aż po przyszłość z AI. Praktyczny przewodnik dla CISO i menedżerów IT.
Incident Response Plan 2025: Jak Przygotować Firmę na Cyberatak? - Wymogi NIS2, Reguła 24/72h i Tabletop Exercises
W 2025 pytanie brzmi "kiedy", nie "czy" nastąpi atak. Zarząd ponosi osobistą odpowiedzialność do 600% wynagrodzenia, NIS2 wymaga raportowania w 24/72h, a "wyciągnięcie wtyczki" może zniszczyć dowody. Praktyczny przewodnik budowy IRP - od CSIRT po Tabletop Exercises.
MSSP 2025: 4 Pułapki Przy Wyborze Dostawcy Managed Security (I Dlaczego Własny SOC Kosztuje 5x Więcej)
Własny SOC 24/7 wymaga 5-6 analityków na etat i kosztuje 5x więcej niż myślisz. Odkryj 4 krytyczne błędy przy wyborze MSSP, różnicę MSP vs MSSP, prawdę o "15 minutach reakcji" i dlaczego outsourcing nie zwalnia zarządu z odpowiedzialności NIS2.
Komentarze
Ładowanie komentarzy...