What Is Managed Detection and Response (MDR)?

Managed Detection and Response (MDR) is a 24/7 managed security service where an external team uses security telemetry and analytics to detect, investigate, and guide or execute response actions to contain confirmed incidents.

MDR is best for organizations that do not have an internal cybersecurity operations team or need expert-led threat hunting to reduce attacker dwell time.

MDR delivers four functions that distinguish it from basic monitoring:

  • Continuous monitoring across endpoints, networks, and cloud environments to capture threat signals in real time.
  • Proactive threat hunting to identify hidden vulnerabilities and bad actors before they trigger alerts or achieve their objectives.
  • Incident investigation by experienced analysts who determine attack scope and severity, along with business impact.
  • Rapid response actions, such as isolating compromised systems and terminating attacker processes.

When an MDR analyst confirms a threat, they take immediate containment actions rather than simply notifying your team and waiting for internal resources to respond.

What Is a Managed Security Service Provider (MSSP)?

A managed security service provider (MSSP) is an outsourced team that administers, monitors, and maintains your security infrastructure and tools. MSSPs handle your day-to-day operations and forward alerts to your internal team for further investigation and response.

MSSPs are best suited for organizations looking for reliable tool administration and compliance oversight and do not want to hire specialized cybersecurity engineers for the different technologies they deploy.

MSSPs deliver services such as:

  • Firewall administration
  • Patch deployment
  • Vulnerability scanning
  • Log collection
  • Compliance reporting (e.g., for ISO 27001, PCI DSS, and HIPAA)

When security tools generate alerts, MSSPs forward notifications to your team for investigation and response.

Key Differences: MDR vs MSSP

MDR providers actively hunt threats and execute containment actions, while MSSPs manage security infrastructure and forward alerts to your team. While MDR stops threats directly, MSSP notifies you to act. 

Other aspects that make MDR distinct from MSSP are as follows:

Aspect MDR MSSP
Primary Focus Active threat detection and immediate response Security infrastructure management and compliance
Core Technology Endpoint Detection and Response (EDR) / Extended Detection and Response (XDR) platforms, behavioral analytics, threat intelligence feeds, and SOAR for orchestration Firewalls, intrusion prevention systems, SIEM for log aggregation, vulnerability scanners, and patch management tools
Reactive vs. Proactive Proactive threat hunting to find hidden attackers before alerts fire Reactive monitoring that responds to signature-based detections and policy violations
Alert Fidelity Human analysts investigate alerts that come in and eliminate false positives before the alerts reach the escalation stage, so you receive only validated incidents Automated correlation forwards high-volume alerts to your team; you handle triage and validation
Reporting and Compliance Incident reports with root cause analysis, MITRE ATT&CK mapping, and actionable remediation steps Compliance dashboards, log retention for audits, and regulatory reporting templates
Expertise Level and Oversight 24/7 access to threat hunters, incident responders, and digital forensics experts Security engineers and system administrators focused on tool maintenance
Response Authority Takes direct action: isolate compromised hosts, block malicious IPs, terminate attacker processes Document findings and notify your team; your staff executes all containment actions
Cost and Pricing Model Per-endpoint or per-user pricing with response services included in subscription Device count or log volume pricing; investigation and response are usually billed separately or excluded

Can MSSPs Provide MDR?

Some MSSPs market MDR-like capabilities, but a service provider can only make claims that they are selling an MDR solution if the solution can:

  • Run continuous threat hunting by experienced analysts
  • Provide immediate incident investigation with full forensic context
  • Have direct containment authority to stop active breaches.

MSSPs lacking any of these elements are not providing true MDR capabilities. Consider the following factors when evaluating vendors:

  • Alert forwarding without analysis: If the provider sends SIEM or EDR alerts directly to you without human investigation between detection and notification, you’re receiving tool alerts, and not a MDR service.
  • No proactive hunting: Ask to see three threats their team found last month that didn’t trigger automated alerts. If they can’t provide examples, they’re not doing threat hunting.
  • Response stops at recommendations: Check the SLA. If it says “notify” or “recommend” but not “isolate” or “block,” and everything requires your approval, expect response delays that may not reflect true MDR capabilities.
  • Vague detection coverage: Marketing mentions like “AI-powered” or “advanced analytics” mean nothing without specifics. Credible providers should be able to map their detections to MITRE ATT&CK and can explain which techniques they detect at each stage.
  • No analyst credentials: High analyst-to-customer ratios (e.g., 200+ customers per analyst) indicate a limited depth of investigation. Be sure to ask them about their certifications to verify the team investigating your alerts’ credentials.

Which Model Is Right for Your Organization?

An MDR or an MSSP may be more suitable for your needs, depending on your organization’s security and operational requirements.

For example, MDR may be a better fit if you need active threat response and lack internal security operations expertise. However, an MSSP may be a better choice if you need security infrastructure management and already have staff who can handle internal alert investigation. 

Decision Factor Choose MDR When Choose MSSP When
Security Needs You face targeted attacks that require active threat hunting and immediate containment.

You need analysts to investigate threats and execute responses promptly, without waiting for your approval.

 Your security infrastructure needs reliable management, but you still have a team that can handle alert investigations.

You prioritize maintaining firewalls and compliance logging.
Risk Profile and Threat Environment You operate in high-value sectors where cybercriminals may specifically target you.

You have faced recent breaches or regulatory scrutiny, which increased pressure on you to detect issues rapidly.

 Your environment primarily faces opportunistic attacks, which signature-based tools can catch effectively.

 

You have standardized IT with lower targeting, so you have lower ongoing threat-hunting needs.
Compliance Requirements Regulations for your industry require you to show incident response capabilities and present forensic reports.

You may need root cause analysis, MITRE ATT&CK mapping, and evidence documentation for breach notifications and auditors.

 Your compliance team focuses on preventive controls and log retention activities.

You need proof that security tools are deployed correctly and that they are generating audit trails.
Budget and Internal Resources Your security team lacks investigation expertise, or you are unable to staff 24/7 operations.

MDR’s higher cost might offset the expense of hiring threat hunters, incident responders, and forensic analysts.

 Your budget requires cost-effective monitoring.

You also have personnel who can handle alert triage and response coordination during business hours.
Response and Coverage You need immediate containment actions to be executed, also without your approval. You need alerts and recommendations, but prefer to control all response actions internally.

Your service provider can notify you of threats and suggest remediation steps while your staff executes the containment measures.

 

When To Combine MSSP and MDR

You can combine MSSP and MDR if you need both infrastructure management and active threat response but lack internal staff to handle both.

MSSP manages security tools and compliance, while MDR hunts threats and executes containment. Each service addresses distinct operational needs without overlapping.

Benefits and considerations of an integrated approach

An integrated MSSP-MDR approach can reduce your total security operations costs while delivering broader coverage than either service alone; however, this requires more coordination to prevent security gaps.

With this approach, you gain infrastructure oversight from an MSSP and expert-led threat response from an MDR, so you don’t have to hire specialized staff for both disciplines.

How the integrated model works:

MSSP manages your security infrastructure, including but not limited to firewall rules, patch schedules, vulnerability scanning, compliance logging, and tool maintenance.

On the other hand, MDR handles threat detection, proactive threat hunting, security alert investigation, and executes an immediate incident response.

Some organizations benefit more from an integrated model than from singling out a solution. This is even more true if you need comprehensive security coverage but lack the resources to build a full internal security operations team. Some of the organizations that may fit this criteria include:

  • Mid-market enterprises with limited security staff need comprehensive coverage without building an internal SOC. An MSSP handles operational overhead, while MDR provides expert-led threat response.
  • Hybrid environments spanning on-premises and multi-cloud infrastructure should have access to an MSSP to maintain consistent security policies across different platforms. At the same time, MDR correlates threats across the entire attack surface.
  • Regulated industries need preventive controls (MSSP) for audit documentation and active threat response (MDR) for incident investigation. Both of these are required by frameworks like PCI DSS, HIPAA, and GDPR.

Key considerations when running both services

Three critical considerations determine whether the combined model succeeds:

  • Do both providers share telemetry and incident data? This helps to eliminate blind spots.
  • Have clear escalation workflows been established? If so, MSSP alerts can reach MDR analysts without delays.
  • Have response authority boundaries been defined? For example, which provider handles containment, and for which threat types? This helps to prevent confusion during active incidents.

The combined approach costs less than hiring specialized staff for both infrastructure management and threat operations. Additionally, a blended service pricing typically remains below the cost of a fully staffed internal SOC while delivering broader coverage.

Questions To Ask MSSPs and MDR Providers

Use these questions to evaluate whether a service provider delivers the capabilities you need and can prove measurable cybersecurity outcomes.

1. Walk us through your end-to-end workflow from alert to containment.

Ask which process is automated versus human-led at each stage. Credible service providers should be able to articulate transparent processes that showcase how telemetry becomes actionable intelligence and lead to threat disruption.

2. What technologies and data sources are required to deliver reliable outcomes?

Ask which data sources are mandatory, what integrations exist to support your current stack, and whether their platform is capable of ingesting telemetry from your existing investments.

3. Can you demonstrate detection coverage for the threats relevant to our organization?

Request for examples of how the provider detects attack techniques specific to your industry needs. Ideally, the service provider should reference MITRE ATT&CK to show the tactics and strategies they identify.

4. Are you able to provide metrics showing continuous improvements in analysis time?

Ask for trend data on mean time to detect (MTTD), mean time to investigate (MTTI), and mean time to respond (MTTR), which are the most important data to record when it comes to threat hunting. While not applicable for all service providers, those with better results should be able to demonstrate improvement for this data over time.

5. What are three new types of threats you can now identify due to improvements you’ve made in the last three months?

The answers to this question reveal whether the provider actively strengthens their threat detection capabilities or is still relying on static rules. Strong answers may describe specific campaigns or techniques that have been recently incorporated, but you’ll need to know about them first to use the information as a benchmark here.

6. What is your approach to false positives, and how do you quantify them internally?

Ask for two numbers: their internally measured false-positive rate and the customer-experienced false-positive rate. The gap shows how much investigation they perform before escalating.

7. What authority do you have to respond, and what actions can you take without waiting on us?

Understand which containment actions occur automatically, which require analyst approval, and which need your authorization. They should be able to set clear boundaries to prevent unnecessary delays when incidents occur.

How Group-IB Delivers Stronger Outcomes with Managed XDR

The choice between MDR and MSSP depends on whether you need an active, immediate threat response or infrastructure management. MDR hunts threats and executes containment, while MSSP maintains your security tools and forwards alerts for your further action. 

If you need both coverage and response authority without building internal capabilities, you’ll need a solution that delivers true MDR outcomes. Group-IB Managed XDR combines 24/7 threat hunting with immediate containment authority across endpoints, network, email, and cloud environments. The platform correlates signals across multiple attack surfaces to detect multi-stage attacks that single-point tools may not.

“Smart Alert in Group-IB Managed XDR has become a cornerstone of our incident response workflows. Our team has used Group-IB MXDR across hundreds of IR cases, and Smart Alert consistently cuts through the noise, saving hours of manual triage. It enables us to act faster, with greater confidence, and redirect our focus to critical decisions that actually mitigate risk.” – Abdulmohsen Almuqati, Head of Group-IB’s DFIR Practice, META

Furthermore, our Threat Intelligence Platform enriches every security alert with adversary context, MITRE ATT&CK mapping, and threat actor TTPs. This enables your team to prioritize incidents based on actual risk rather than alert volume.

Talk to Group-IB experts to learn how Managed XDR enables you to combat evolving cyber threats through an integration of advanced security technologies and automated threat countermeasures.