Cybersecurity Terms Explained | Learning Hub | Eye Security

What is an incident response service? IR service explained

Written by Eye Security | Aug 7, 2025 9:00:00 AM

When a cyberattack hits, every second counts. Whether it’s ransomware locking up systems or a data breach exposing sensitive information, how you respond can mean the difference between a quick recovery and lasting damage. That’s where incident response comes in: a structured, expert-led process that helps businesses detect, contain, and recover from security incidents at the necessary speed.

Incident response teams are built to quickly identify, contain, and resolve security incidents, ensuring smooth operations and reducing losses. In this article, you learn what an incident response service involves, its key components, and how it protects.

The takeaways

  • A strong incident response capability limits damage, downtime, and legal risk, helping restore operations quickly and protect reputations.
  • Effective incident response goes beyond detection. It includes containment, recovery, and continuous improvement based on real-world learnings.
  • Partnering with expert providers ensures readiness, giving you access to 24/7 support, specialist tools, and proven playbooks.
  • Regulatory frameworks increasingly demand response plans, including GDPR, PCI DSS, NIS2, ISO 27001, and national regulations like BSIG.
  • An incident is a business risk. A well-prepared response strategy is essential for resilience and trust.

How do we define incident response?

Incident response is a component of cybersecurity that enables organisations to detect, respond to, and recover from security incidents in a timely manner. It is a set of procedures and processes that help minimise the impact of a security breach, maintain trust, and ensure regulatory compliance.

Incident response minimises the impact of an attack

IR helps organisations to quickly identify and contain an incident, minimise the damage, and restore operations. A well-planned incident response plan helps reduce the risk of financial loss, reputational damage, and legal liability. 

Effective incident response maintains trust

An incident response plan (IRP) demonstrates commitment to security. It helps maintain trust with customers, partners, and stakeholders, and ensures that the organisation’s reputation is protected.

Incident response is essential for regulatory compliance

Many regulatory bodies require that organisations have an incident response plan in place. While GDPR does not explicitly say “you must have an incident response plan”, it requires organisations to detect, assess, and report data breaches within 72 hours (Articles 33 and 34). GDPR also requires organisations to implement “appropriate technical and organisational measures” (Article 32), which includes readiness for incidents.

PCI DSS is more direct. Requirement 12.10 explicitly states that organisations must implement an incident response plan for cardholder data breaches. It includes clear expectations on testing, roles and responsibilities, reporting, and containment.

In Germany, for critical infrastructure operators, incident handling is mandatory under BSIG (BSI-Gesetz). The BSI-Gesetz requires implementation of an incident response strategy and ongoing testing.

The NIS2 Directive (EU, effective 2024/2025) requires incident handling capabilities for “essential” and “important” entities. While it doesn't use the term IRP uniformly, it mandates processes for detection, reporting, and response to security incidents.

Finally, the international standards ISO/IEC 27001 & 27035, and in particular ISO/IEC 27001:2013/2022 (Annex A) and ISO 27035 (specifically for incident management), define clear requirements for establishing, operating, and maintaining an incident response process. These are often used as a benchmark for regulatory audits and supplier security assessments.

What are the key components of an incident response service?

A high-quality incident response (IR) service provides a structured, proactive approach to detecting, containing, and recovering from cybersecurity incidents. Whether delivered as part of a managed service (like MDR) or on-demand, a strong IR service typically includes the following key components:

1. Preparation and readiness

  • Incident response plan (IRP) creation or validation
  • Runbooks and playbooks for common attack types (e.g. ransomware, business email compromise)
  • Roles and responsibilities clearly defined
  • Exercises and simulations to test readiness
  • Threat modeling and risk assessments

Goal: Ensure the organisation is ready to act decisively and knows what to do before an incident occurs.

2. Detection and triage

  • 24/7 threat monitoring (typically via SOC, SIEM, or XDR platforms)
  • Alert validation and triage
  • Integration of threat intelligence for additional context
  • Suspicious activity correlation across endpoints, networks, and cloud environments
  • Rapid alert-to-action processes

Goal: Quickly identify real threats and prioritise them for investigation.

3. Investigation and analysis

  • Root cause analysis
  • Identification of the attack vector (e.g. phishing, vulnerability exploit)
  • Definition of the incident scope
  • Digital forensics (log analysis, memory capture, malware analysis)
  • Mapping of attacker behavior (e.g. using MITRE ATT&CK)

Goal: Understand what happened, how it happened, and what systems or data were affected.

4. Containment and eradication

  • Short-term containment measures to limit the attack
  • Isolation of affected systems
  • Credential revocation or resets
  • Malware removal or system reimaging
  • Removal of persistence mechanisms and backdoors

Goal: Stop the attacker, prevent further damage, and remove their access.

5. Recovery and restoration

  • Restore systems and data from clean backups
  • Patch exploited vulnerabilities
  • Rebuild trust in affected environments
  • Validate full removal of attacker presence
  • Post-recovery monitoring for re-entry attempts

Goal: Bring business operations back online safely and confidently.

6. Post-incident reporting and recommendations

  • Comprehensive incident report including timeline, impact, and root cause
  • Support for regulatory or compliance reporting (e.g. GDPR)
  • Executive summary for stakeholders
  • Technical and procedural remediation recommendations
  • Lessons learned session and follow-up improvements

Goal: Improve long-term security posture and meet reporting obligations.

What are the components of an incident response plan development?

Preparation is the cornerstone of an IRP, involving assessing vulnerabilities and creating an action plan for potential cybersecurity threats. This proactive approach ensures that when an incident occurs, the organisation is ready.

1. Purpose and scope

  • Define the objective of the IRP (e.g., minimize damage, restore operations, meet compliance requirements).
  • Specify the systems, locations, and types of incidents the plan applies to.
  • Clarify what constitutes a “security incident” 

2. Roles and responsibilities

Designate an Incident Response Team (IRT) and their roles:
    • IR manager/lead
    • Analysts (tiers 1–3)
    • Legal/compliance
    • Communications/PR
    • Executive sponsor
    • IT support
  • Include contact lists and escalation paths.
  • Define decision-making authority (e.g., who can approve containment actions or external communication)

3. Incident classification and severity levels

  • Define categories (e.g., malware, data breach, insider threat, DDoS, ransomware).
  • Assign severity levels (e.g., low, medium, high, critical) based on impact and urgency.
  • Align with business impact thresholds and regulatory consequences.

4. Incident response lifecycle and procedures

Often based on NIST 800-61 or ISO/IEC 27035, this section covers:

Preparation

  • Tools, training, and policies required to enable a response
  • Access control, backup procedures, logging, and communication protocols

Detection and analysis

  • How incidents are identified (e.g., SIEM alerts, user reports, threat intel)
  • Triage and investigation procedures
  • How to determine scope, vector, and timeline

Containment, eradication, and recovery

  • Short- and long-term containment steps
  • Malware removal, credential resets, patching
  • Restoration from backups
  • System validation and monitoring

Post-incident activity

  • Root cause analysis
  • Documentation of actions taken
  • Lessons learned and corrective measures
  • Report preparation (internal and external)

Communication and escalation protocols

  • Define internal communication procedures (who needs to know, when, and how).
  • Define external communication (customers, regulators, media).
  • Prepare pre-approved templates for breach notifications and press releases.
  • Establish a chain of command for escalations.

Legal, regulatory, and compliance considerations

  • Map required breach notifications (e.g., GDPR 72-hour rule, HIPAA, PCI DSS).
  • Detail reporting timeframes and authorities (e.g., DPA, law enforcement, SEC).
  • Include guidance for working with legal counsel, insurance, and auditors.

Tools and resources

  • List of detection, response, and forensic tools (e.g., EDR, SIEM, XDR, forensic kits).
  • Access credentials, backup solutions, secure communication channels.
  • Contact details for third-party vendors or retainer-based IR support.

Testing and training

  • Schedule for tabletop exercises, red team simulations, or breach drills.
  • Responsibilities for updating the IRP based on test results.
  • Ongoing training requirements for team members.

Plan maintenance and version control

  • Assign ownership for updates and reviews.
  • Include version history, change log, and review cycle (e.g., annual or after major incidents).
  • Track when the plan was last tested or reviewed.

What is the role of detection and analysis in incident response contexts?

Monitoring and detection capabilities are critical to reducing the average time it takes to identify a breach, often measured in months, with industry reports citing an average of 194 days. Security Information and Event Management (SIEM) systems play a central role by aggregating and analysing data from diverse sources across the network, providing a comprehensive overview of security events.

The integration of SIEM with Endpoint Detection and Response (EDR) tools significantly enhances security posture. While SIEM offers network-wide visibility, EDR focuses on continuous monitoring of endpoints, such as laptops, servers, and mobile devices, to detect and respond to threats at the device level. EDR solutions leverage behavioral analysis techniques to identify abnormal or suspicious activities in real-time, which often serve as early indicators of potential security incidents.

Automation within EDR solutions enables immediate action, such as isolating compromised devices to prevent further spread of malware or unauthorized access. Expanding this approach, Managed Extended Detection and Response (XDR) solutions unify multiple detection sources, including endpoints, networks, cloud environments, and applications, to improve threat correlation and accelerate incident detection.

What are the most typical containment and eradication strategies?

Once a security incident is identified and analysed, the next priority is to contain the threat and eradicate it from the environment. These phases are critical to stopping attacker activity, limiting damage, and preparing for safe recovery.

Containment strategies

Containment focuses on isolating the threat to prevent it from spreading or causing further harm. Typical containment strategies include:

  • Network segmentation: Limiting lateral movement by isolating affected systems or network zones.
  • Endpoint isolation: Disconnecting compromised devices from the network to stop attacker communication or data exfiltration.
  • Account lockdown: Disabling or resetting credentials (especially privileged accounts) that may have been compromised.
  • Blocking malicious domains/IPs: Updating firewall or DNS rules to prevent connections to known malicious infrastructure.
  • Disabling vulnerable services: Temporarily shutting down services or ports used in the attack until properly secured.

Containment measures can be short-term (quick actions to halt active threats) or long-term (more permanent changes to prevent recurrence).

Eradication strategies

Eradication involves removing the root cause of the incident, cleaning up malicious artifacts, and eliminating any attacker persistence. Common eradication strategies are:

  • Malware removal: Using EDR or antivirus tools to remove malware from affected endpoints and servers.
  • System reimaging: Rebuilding compromised systems from clean, verified images when malware cannot be reliably removed.
  • Credential reset: Resetting user and administrative passwords, especially if credential theft or lateral movement was involved.
  • Patching vulnerabilities: Addressing the exploited vulnerability, whether it's unpatched software, misconfigurations, or weak security controls.
  • Removing persistence mechanisms: Identifying and deleting backdoors, scheduled tasks, rogue user accounts, or registry changes that could allow re-entry.

Both containment and eradication require coordination, clear roles and responsibilities, and documentation. These steps are often guided by predefined playbooks for specific attack types, such as ransomware or business email compromise.

When executed effectively, containment and eradication set the foundation for successful recovery and reduce the risk of reinfection or follow-up attacks.

What happens during the recovery and restoration processes?

After a cyber incident has been contained and eradicated, the focus shifts to recovery and restoration, i.e. the crucial phase where affected systems are brought back online and operations return to normal. Recovery a structured process aimed at rebuilding trust, verifying system integrity, and ensuring long-term resilience.

1. Restoring systems from clean backups

One of the first steps in recovery is restoring affected systems using backups that are verified to be clean and uncompromised. This ensures that the organisation isn’t reintroducing malware or malicious configurations during the recovery process.

2. Patching vulnerabilities

If the incident exploited a specific weakness, such as an unpatched vulnerability or misconfiguration, it must be resolved before restoring normal operations. This helps prevent the same attack vector from being used again.

3. Validating system integrity

Before reintroducing systems into the production environment, they must be thoroughly tested. This includes scanning for malware, checking configuration baselines, and confirming that security controls (like logging and access controls) are intact.

4. Credential resets and trust rebuilding

If attacker activity involved stolen credentials or account misuse, affected passwords must be reset. In high-risk cases, this may include rotating API keys, SSH keys, or even conducting full Active Directory hygiene.

5. Post-recovery monitoring

Just because the visible signs of compromise are gone does not mean the threat is fully neutralised. Organisations should implement heightened monitoring during and after the recovery phase to detect any signs of persistence or re-entry attempts. This is often referred to as “watch mode.”

6. Communication and coordination

Clear communication with stakeholders, including IT, legal, leadership, and in some cases customers or regulators, is essential during recovery. It ensures alignment on timelines, risks, and mitigation progress.

7. Business continuity and lessons learned

The recovery phase should also include a review of how well business continuity plans performed. What went well? What gaps were identified? These insights should feed into an after-action review and lead to updates in the incident response plan, processes, and technology stack.

What takes place during the post-incident review and lessons learned?

The final, yet arguably most valuable, stage of any incident response process is the post-incident review. Once the dust has settled, it's time to step back, assess what happened, and turn the experience into actionable insights. This review is critical for improving future response capabilities, strengthening defences, and building long-term cyber resilience.

1. Reconstructing the timeline

The incident response team works with logs, forensic data, and internal reports to build a clear, chronological timeline of the attack. This includes:

  • Initial entry point
  • Lateral movement
  • Data access or exfiltration
  • Detection and response actions taken

The timeline helps identify what was missed, what was detected too late, and where improvements can be made.

2. Root cause analysis

Understanding how the incident happened is essential. Was it due to a phishing email, an unpatched system, misconfigured access rights, or something else? 

3. Evaluating the response

The review evaluates how well your organisation responded:

  • Were roles and responsibilities clear?
  • Were communication channels effective?
  • Were decisions made quickly and confidently?
  • Did the incident response plan hold up under pressure?

This is a chance to identify any bottlenecks or breakdowns in process.

4. Technical and procedural recommendations

The post-incident phase should result in concrete recommendations, such as:

  • Improving detection rules or alert thresholds
  • Updating firewall or EDR configurations
  • Closing security gaps or policy loopholes
  • Training staff on new threats or tactics

These insights should feed directly into your broader security roadmap.

5. Stakeholder debrief

Non-technical stakeholders (e.g. executives, legal, comms) should receive a clear, non-technical summary of the incident: what happened, how it was handled, and what will be done to prevent recurrence. Transparency builds trust and shows control.

6. Plan and playbook updates

If any part of the incident response plan, runbooks, or escalation matrix failed or fell short, it should be updated immediately. This might also include adjusting severity classifications or refining containment protocols.

7. Optional: External reporting

Depending on the scope and impact of the incident, you may need to provide final reports to regulators, insurers, or customers. The post-incident review helps ensure those reports are accurate, consistent, and complete.

Summary

A well-designed incident response service includes preparation, detection, investigation, containment, recovery, and post-incident review. Each phase plays a vital role in minimising damage, maintaining business continuity, and fulfilling legal and regulatory obligations.

The article explored:

  • Key components of incident response services, including SIEM, EDR, containment tactics, and restoration procedures
  • Steps for developing an incident response plan, from defining scope and responsibilities to regulatory compliance and communication protocols
  • Post-incident activities, such as reporting, lessons learned, and continuous improvement
  • Industry-specific strategies, showing how sectors like healthcare, finance, and manufacturing adapt IR plans to their unique risks

Frequently Asked Questions

What is an incident response service?

An incident response service prepares organisations to effectively handle security incidents by enabling swift action to mitigate threats and facilitate recovery. This proactive approach minimises damage and enhances overall security posture.

What are the key components of an incident response plan?

An effective incident response plan must encompass early detection, containment and eradication strategies, post-incident analysis, and continuous improvement. These components are essential to ensure a swift and successful response to incidents.

How do different industries tailor their incident response strategies?

Different industries tailor their incident response strategies to meet specific challenges and comply with regulatory requirements, ensuring effective management of incidents. For example, healthcare emphasises patient data privacy, while logistics focuses on supply chain disruptions.

Why is continuous monitoring important for incident response?

Continuous monitoring is essential for early threat detection and rapid response to incidents, which helps maintain robust protection against evolving cyber threats. This proactive approach significantly mitigates potential damages from breaches.

How can partnering with Managed Service Providers enhance incident response?

Partnering with Managed Service Providers enhances incident response by offering access to experienced professionals, advanced cybersecurity solutions, and continuous monitoring and response services. This not only strengthens incident response capabilities but also improves overall security posture.