Incident response is the process of detecting, analyzing, and containing a cybersecurity breach or attack. Having a swift and effective incident response plan is crucial for organizations to minimize damages and restore normal operations after an incident. The incident response process generally consists of 5 key phases:
Preparation
The preparation phase involves putting mechanisms and policies in place ahead of time to enable rapid detection and response to incidents. This includes:
- Establishing an incident response team and defining roles and responsibilities
- Creating incident response procedures and playbooks
- Implementing controls like firewalls, intrusion detection systems, and anti-malware to prevent and detect threats
- Conducting training and exercises for the incident response team
- Establishing communication plans and notification procedures
- Procuring equipment and tools to facilitate investigation and remediation
- Developing agreements with external partners and law enforcement about assistance during incident response
Thorough preparation enables faster decision making and coordinated action when an actual incident occurs. It’s estimated that organizations who invest resources in preparation and planning for incident response have security breaches that cost $1.2 million less on average.
Detection
The detection phase is when abnormal activity or a potential security incident is first discovered. Incidents can be detected through:
- Intrusion detection systems sending alerts
- Anti-malware software identifying threats
- Monitoring tools noticing anomalous traffic or behavior
- Error reports from applications or infrastructure
- Notifications from external parties of compromised accounts or data
- Users reporting suspicious activity
It’s critical that organizations have strong monitoring capabilities across their environment – including networks, endpoints, cloud services, etc. – to maximize the chances of early detection before major damage occurs.
Analysis
Once a potential incident has been detected, the analysis phase involves gathering information to determine if it is a confirmed incident, understand the scope of impact, and identify the best containment and recovery strategies. Analysis actions include:
- Reviewing related monitoring data like IDS alerts and system logs
- Researching threat intelligence on new attacker tools or techniques
- Conducting forensic examination of compromised systems
- Analyzing suspicious files or activity
- Identifying which systems, networks, accounts, or data may be affected
- Determining the timeline and progression of the incident
Thorough analysis is important to define the nature of the incident and determine the appropriate response. However, analysis should progress quickly to initiate containment measures before attackers can cause more damage.
Containment
Once the analysis provides sufficient information on the incident, the next phase is to contain it. Containment aims to limit the impact of the incident by preventing the attack or compromise from spreading further. Containment actions include:
- Blocking suspicious IP addresses
- Taking infected systems offline
- Shutting down affected services and accounts
- Isolating and disconnecting infected networks
- Blocking unusual outbound network traffic
- Disabling access for compromised user accounts
Containment helps stop additional systems from being accessed or data from being exfiltrated, while the organization works to eradicate and recover from the incident.
Eradication
Eradication involves removing components of the attack/compromise from the environment. The goal is to eliminate the attacker’s presence and return systems to a clean state. Eradication may involve:
- Identifying and blocking all malicious scripts, files, and malware
- Conducting additional monitoring to verify all threats have been eliminated
- Rebuilding and reinstalling operating systems on compromised systems
- Changing passwords and deactivating malicious user accounts
- Patching vulnerabilities that were exploited
- Improving defenses to prevent similar incidents
Thorough eradication is necessary to ensure the attacker has been fully removed before restoring business functions and services impacted by the incident.
Recovery
The recovery phase aims to resume normal operations and service availability after containing and eradicating an incident. Recovery actions may include:
- Reconnecting networks and bringing systems back online
- Restoring data from clean backups if needed
- Confirming that all systems are updated and securely configured
- Monitoring systems for suspicious activity as users reconnect
- Communicating status updates to executives and stakeholders
- Offering guidance to affected customers or partners
The timeliness and effectiveness of recovering business functions after an incident will determine the overall business impact. Thorough testing and documentation of recovery procedures during preparation improves recovery outcomes.
Lessons Learned
Each incident response should conclude with a lessons learned phase. The goal is to identify successes, failures, and improvements that will strengthen future incident handling. Lessons learned activities include:
- Conducting a ‘hot wash’ meeting with all involved parties shortly after resolution
- Holding a formal lessons learned meeting weeks or months later with a wider audience
- Documenting findings in an after action report or updated response plan
- Identifying gaps in preparation, detection, analysis, containment, eradication, or recovery
- Determining which tools, resources, training, or procedures would improve response
- Incorporating lessons into updated incident response procedures and policies
Continuous improvement of incident response capabilities is critical for enhancing the organization’s resilience.
Conclusion
An efficient incident response process enables organizations to quickly detect, analyze, contain, eradicate, and recover when cyber attacks occur. The 5 key phases are preparation, detection, analysis, containment, eradication, and recovery. Effective incident response relies on planning and practice throughout these phases to minimize business disruption. Conducting a lessons learned exercise after each incident also facilitates continuous enhancement of response capabilities over time.
Organizations should invest in maturing their incident response program to improve readiness. Developing detailed playbooks, training personnel, conducting simulations, and implementing robust security controls are all part of incident response preparation. When incidents inevitably occur, following established playbooks and procedures will enable a swift, coordinated, and effective response across all 5 phases.
Here is a summary table of the 5 incident response phases and key activities involved in each phase:
| Phase | Key Activities |
|---|---|
| Preparation |
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| Detection |
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| Analysis |
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| Containment |
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| Eradication |
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| Recovery |
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