Incident Response Planning and Execution for Enterprise Networks

In today's digital landscape, cybersecurity incidents are not a matter of if, but when. A well-prepared incident response plan is crucial for minimizing damage, reducing recovery time, and maintaining stakeholder trust. This guide provides a comprehensive approach to incident response planning and execution for enterprise networks.

1. Incident Response Plan Components

A comprehensive incident response plan should include the following components:

• Incident Response Team Structure
• Incident Classification and Prioritization
• Response Procedures
• Communication Plan
• Tools and Resources
• Post-Incident Analysis

2. Incident Response Team Structure

Define clear roles and responsibilities for your incident response team:

• Incident Response Manager
• Technical Lead
• Security Analyst
• Network Administrator
• Legal Counsel
• Public Relations Specialist

3. Incident Classification and Prioritization

Develop a system for classifying and prioritizing incidents. For example:

Severity Levels:
1 - Critical: Significant impact on critical systems
2 - High: Potential for significant impact if not addressed quickly
3 - Medium: Limited impact, but requires attention
4 - Low: Minimal impact, can be addressed during normal business hours

Priority Matrix:
| Severity | Urgency | Priority |
|----------|---------|----------|
| Critical | High    | P1       |
| High     | High    | P2       |
| Medium   | High    | P3       |
| Low      | High    | P4       |
| Critical | Low     | P2       |
| High     | Low     | P3       |
| Medium   | Low     | P4       |
| Low      | Low     | P5       |

4. Response Procedures

Develop detailed procedures for each phase of the incident response lifecycle:

1. Preparation: Ensure tools, resources, and training are in place.
2. Detection and Analysis: Identify and confirm the incident.
3. Containment: Prevent further damage.
4. Eradication: Remove the threat from the environment.
5. Recovery: Restore systems to normal operation.
6. Post-Incident Activity: Learn from the incident and improve processes.

Malware Incident Playbook:
1. Isolate affected systems
2. Collect and preserve evidence
3. Identify malware type and behavior
4. Remove malware and associated artifacts
5. Patch vulnerabilities
6. Restore from clean backups
7. Monitor for reinfection

5. Communication Plan

Establish clear communication channels and protocols:

• Internal stakeholders (executives, employees)
• External stakeholders (customers, partners)
• Regulatory bodies
• Law enforcement (if necessary)

6. Tools and Resources

Equip your team with the necessary tools for effective incident response:

• SIEM (Security Information and Event Management) system
• Endpoint Detection and Response (EDR) tools
• Network forensics tools
• Malware analysis sandbox
• Threat intelligence platforms

$computerInfo = Get-ComputerInfo
$processes = Get-Process
$connections = Get-NetTCPConnection
$services = Get-Service

$report = @{
    ComputerInfo = $computerInfo
    Processes = $processes
    Connections = $connections
    Services = $services
}

$report | ConvertTo-Json | Out-File "C:\IncidentResponse\initial_report.json"

7. Post-Incident Analysis

After resolving an incident, conduct a thorough post-incident analysis:

• Timeline of events
• Effectiveness of the response
• Areas for improvement
• Lessons learned
• Recommendations for preventing similar incidents

8. Regular Testing and Updating

Regularly test and update your incident response plan:

• Conduct tabletop exercises
• Perform full-scale simulations
• Update the plan based on lessons learned and changes in the threat landscape

Invoke-AtomicTest T1003.001 -TestNumbers 1,2

9. Integration with Business Continuity and Disaster Recovery

Ensure your incident response plan aligns with and complements your organization's broader business continuity and disaster recovery plans.

10. Compliance and Legal Considerations

Ensure your incident response plan meets relevant regulatory requirements:

• GDPR
• HIPAA
• PCI DSS
• Industry-specific regulations

11. Incident Response Metrics

Establish metrics to measure the effectiveness of your incident response program:

• Mean Time to Detect (MTTD)
• Mean Time to Respond (MTTR)
• Incident resolution time
• Number of incidents by type and severity
• Cost per incident

import pandas as pd
from datetime import datetime

def calculate_metrics(incidents_df):
incidents_df['detected_time'] = pd.to_datetime(incidents_df['detected_time'])
incidents_df['occurred_time'] = pd.to_datetime(incidents_df['occurred_time'])
incidents_df['resolved_time'] = pd.to_datetime(incidents_df['resolved_time'])

mttd = (incidents_df['detected_time'] - incidents_df['occurred_time']).mean()
mttr = (incidents_df['resolved_time'] - incidents_df['detected_time']).mean()

return mttd, mttr

# Usage
incidents_df = pd.read_csv('incidents.csv')
mttd, mttr = calculate_metrics(incidents_df)
print(f"Mean Time to Detect: {mttd}")
print(f"Mean Time to Respond: {mttr}")

Conclusion

An effective incident response plan is crucial for minimizing the impact of security incidents on your enterprise network. By following this guide, you can develop a robust plan that enables your organization to respond quickly and effectively to a wide range of potential incidents.