Prepare forensic capabilities

Preparing forensic capabilities in advance of a security incident is essential to ensure effective investigation, containment, and resolution of security events. Establishing well-defined processes, tools, and roles for collecting, analyzing, and preserving evidence allows your organization to accurately determine the root cause of an incident and take appropriate remedial actions. Prepared forensic capabilities also help ensure that evidence is handled in a manner that preserves its integrity for legal or regulatory purposes if needed.

1. Define forensic investigation processes: Develop a structured approach for conducting forensic investigations. This should include clear guidelines for collecting evidence, analyzing data, documenting findings, and handling sensitive information. Document and standardize processes for various types of incidents (e.g., data breaches, ransomware attacks), outlining step-by-step procedures for performing investigations.
2. Identify forensic investigation team members: Designate internal personnel responsible for performing forensic investigations, such as Security Analysts or Incident Response Team members. Assign roles and responsibilities to ensure that appropriate team members are involved in collecting and analyzing evidence during an incident. Backup personnel should also be assigned to ensure coverage during off-hours or holidays.
3. Deploy forensic data collection tools: Ensure that the necessary tools are in place for collecting data and performing forensic analysis. Tools such as AWS CloudTrail, AWS Config, Amazon GuardDuty, and AWS Systems Manager can be used to gather information during an investigation. AWS CloudTrail provides logs of API activities, while AWS Config captures configuration changes, helping to identify unauthorized modifications. For deeper analysis, third-party forensic tools or services may also be used.
4. Enable detailed logging and monitoring: Enable logging across all relevant AWS services to capture detailed activity and network information. Use AWS CloudTrail for API activity logging, Amazon VPC Flow Logs for capturing network traffic, and Amazon CloudWatch for monitoring performance metrics and generating alerts. Logs should be retained for an appropriate period to support potential forensic investigations and should be stored securely.
5. Store forensic evidence securely: Ensure that forensic data is stored in a secure location that preserves its integrity and authenticity. Use Amazon S3 with server-side encryption to store logs, evidence files, and other data collected during investigations. Restrict access to forensic data using AWS Identity and Access Management (IAM) policies to ensure that only authorized personnel can access or modify evidence.
6. Implement data preservation policies: Establish policies to preserve forensic data during an incident to prevent it from being overwritten or deleted. Use versioning in Amazon S3 to retain copies of evidence, and enable AWS CloudTrail log file integrity validation to verify that log files have not been altered. Evidence preservation is crucial to ensuring that data remains admissible in legal or regulatory proceedings.
7. Practice forensic readiness through game days: Conduct forensic readiness exercises and incident response game days to ensure that your team is familiar with the processes, tools, and techniques needed for forensic investigations. Practice helps the incident response team develop the skills necessary to respond effectively during an actual security event, including how to collect, analyze, and document evidence.
8. Engage external forensic experts as needed: Establish partnerships with external forensic experts who can assist in investigations during complex incidents. External experts bring specialized expertise, tools, and experience that may be necessary for analyzing advanced threats or malware. Establish retainer agreements ahead of time to ensure rapid access to external resources when needed.
9. Document forensic investigation findings: Create a standardized format for documenting forensic investigation findings, including the incident timeline, evidence collected, analysis results, and conclusions. Proper documentation helps with the post-incident review process and may be required for legal or regulatory purposes.

Supporting Questions:

• What processes and tools are in place to support forensic investigations of security incidents?
• Who are the key personnel involved in forensic investigations, and what are their roles?
• How do you ensure that forensic data is collected, preserved, and documented appropriately?

Roles and Responsibilities:

Security Analyst:

• Responsibilities:
  • Lead forensic investigations, including collecting evidence, analyzing logs, and determining the root cause of incidents.
  • Document findings, preserve evidence, and ensure that the integrity of forensic data is maintained throughout the investigation.

Incident Commander:

• Responsibilities:
  • Coordinate forensic activities during an incident, ensuring that all evidence is collected and analyzed in accordance with established policies.
  • Decide on containment and remediation actions based on forensic analysis findings.

Cloud Administrator:

• Responsibilities:
  • Enable logging across AWS services to support forensic investigations, ensuring that all relevant data is captured and retained.
  • Secure forensic data storage to preserve evidence for potential legal or regulatory requirements.

Artefacts:

• Forensic Investigation Playbook: A playbook outlining the process for conducting forensic investigations, including evidence collection, analysis, and documentation procedures.
• Incident Logs and Evidence Storage: Logs and evidence files collected during investigations, stored securely using Amazon S3 with encryption and access controls.
• Forensic Investigation Reports: Standardized reports documenting forensic analysis findings, including evidence collected, timelines, and root cause conclusions.

Relevant AWS Services:

AWS Forensic and Logging Tools:

• AWS CloudTrail: Captures API activity across your AWS environment, providing logs that are essential for forensic analysis and determining the sequence of events.
• Amazon VPC Flow Logs: Captures network traffic information to and from your VPCs, helping identify unauthorized connections or unusual network activity during investigations.
• AWS Config: Records configuration changes across AWS resources, enabling you to identify unauthorized modifications and assess their impact during an incident.
• AWS Systems Manager: Provides tools like Run Command and Session Manager to help with evidence collection from EC2 instances without needing direct SSH or RDP access.

Data Storage and Preservation Tools:

• Amazon S3: Stores forensic data, such as logs and evidence files, with server-side encryption to maintain the integrity and confidentiality of evidence.
• AWS Identity and Access Management (IAM): Manages access to forensic data, ensuring that only authorized personnel can access or modify evidence during investigations.
• AWS CloudTrail Log File Integrity Validation: Ensures that log files have not been tampered with, providing cryptographic validation to preserve evidence integrity.

Monitoring and Security Tools:

• Amazon GuardDuty: Provides continuous monitoring for malicious activity, generating alerts that can assist in forensic investigations by identifying suspicious activity.
• Amazon CloudWatch: Monitors and logs system metrics, helping detect anomalies and track system performance during incidents, providing additional context for forensic analysis.