No organisation is immune to security incidents. From ransomware attacks and data breaches to insider threats and system compromises, the question is not whether an incident will occur but when. A well-prepared incident response plan (IRP) is the difference between a controlled, efficient response and a chaotic, costly ordeal that causes lasting damage to your organisation.
What Is Incident Response?
Incident response is the organised approach to addressing and managing the aftermath of a security breach or cyber attack. The goal is to handle the situation in a way that limits damage, reduces recovery time and costs, and prevents recurrence. An effective IRP provides clear procedures, defined roles and pre-established communication channels that enable rapid, coordinated action.
The Six Phases of Incident Response
Phase 1: Preparation
Preparation is the most critical phase because it determines how effectively you can respond when an incident occurs. Key preparation activities include establishing a Computer Security Incident Response Team (CSIRT), developing and documenting the IRP, deploying detection and monitoring tools, conducting regular training and exercises, establishing relationships with external parties (law enforcement, forensic specialists, legal counsel) and maintaining up-to-date contact lists and escalation procedures.
Our Operational Security module helps organisations build the monitoring and alerting infrastructure needed for effective incident detection.
Phase 2: Detection and Analysis
Detect potential incidents through multiple sources including SIEM alerts, IDS/IPS notifications, endpoint detection tools, user reports, threat intelligence feeds and anomaly detection. Once detected, analyse the incident to determine its scope, severity, affected systems and potential impact. Classify the incident using a severity scale (critical, high, medium, low) to determine the appropriate response level.
Phase 3: Containment
Containment prevents the incident from spreading and causing further damage. Short-term containment isolates affected systems immediately — disconnecting from the network, blocking malicious IPs or disabling compromised accounts. Long-term containment implements more sustainable measures while maintaining business operations, such as rebuilding systems on clean infrastructure or applying emergency patches.
Phase 4: Eradication
Remove the root cause of the incident from the environment. This may involve removing malware, closing exploited vulnerabilities, patching systems, resetting credentials, rebuilding compromised systems from known-good images and reviewing other systems for similar indicators of compromise.
Phase 5: Recovery
Restore affected systems and services to normal operation. Recovery should be phased, starting with the most critical systems. Monitor restored systems closely for signs of re-infection or persistent threats. Verify the integrity of restored data and systems before returning them to production.
Phase 6: Lessons Learned
Conduct a post-incident review within two weeks of incident closure. Document what happened, what was done well, what could be improved and specific action items for strengthening defences. Update the IRP, detection rules and training based on lessons learned. This phase transforms incidents into organisational learning opportunities.
Building Your Incident Response Team
The CSIRT should include representatives from IT security, IT operations, legal, communications, human resources and relevant business units. Define clear roles including an incident commander (overall coordination), technical lead (technical analysis and remediation), communications lead (internal and external messaging) and documentation lead (evidence preservation and record keeping).
If building an in-house team is not feasible, a dedicated CISO can provide the leadership and coordination needed, supplemented by pre-arranged retainers with external incident response firms.
Communication During Incidents
Effective communication is essential during incidents. Establish pre-approved communication templates for different stakeholder groups including the executive team, employees, customers, regulators and media. Define escalation thresholds that trigger notifications to specific stakeholders. Maintain secure, out-of-band communication channels in case primary systems are compromised.
Tabletop Exercises
Regularly test your IRP through tabletop exercises — facilitated discussions that walk through realistic incident scenarios. These exercises reveal gaps in procedures, test team coordination, build muscle memory and improve response times. Conduct exercises at least annually, varying scenarios to cover different threat types including ransomware, data breaches, insider threats and supply chain compromises.
Legal and Regulatory Considerations
Understand your breach notification obligations under applicable regulations (GDPR 72-hour notification, PDPA 3-day notification, NIS2 24-hour early warning). Engage legal counsel early in significant incidents to manage privilege, preservation obligations and regulatory interactions. Document all response activities thoroughly to demonstrate due diligence.
Tools and Technology
Equip your team with the tools needed for effective response including SIEM platforms for detection and correlation, EDR solutions for endpoint investigation and containment, forensic analysis tools for evidence collection, ticketing systems for incident tracking and threat intelligence platforms for context. Regular vulnerability scanning and penetration testing help identify weaknesses before attackers exploit them.
Conclusion
A well-prepared incident response capability is essential for every organisation. By investing in preparation, training your team and regularly testing your plan, you build the resilience needed to handle security incidents effectively. The organisations that respond best to incidents are those that have practised most. Start building your incident response capability today — the next incident is only a matter of time.