Forensic analysis (also “digital forensics” or “cyber forensics”) is the process of collecting, preserving, analyzing, and presenting digital evidence to investigate security incidents, identify root causes, determine the scope of compromises, and support legal and compliance processes. This process requires specialized techniques to ensure evidence integrity through chain of custody and the use of appropriate forensic tools, being essential for understanding how an incident occurred, identifying responsible parties, supporting legal actions, and improving defenses to prevent future similar incidents.

What is Forensic Analysis?

Forensic analysis is a discipline that:

  • Collects digital evidence from compromised systems
  • Preserves the integrity of evidence for legal use
  • Analyzes data to determine causes and scope
  • Presents findings in legal and compliance processes

Forensic Analysis Types

1. Network Forensics

  • Traffic analysis of network
  • Capture and analysis of packets
  • Attack pattern identification
  • Network event reconstruction

2. Device Forensics

  • Hard disk analysis and storage media
  • Recovery of deleted data
  • Operating system analysis
  • Evidence extraction from mobile devices

3. Application Forensics

  • Application log analysis
  • Vulnerability investigation in code
  • Database analysis
  • User activity reconstruction

4. Memory Forensics

  • RAM memory analysis in real time
  • Active process extraction
  • Malware identification in memory
  • Anomalous behavior analysis

Forensic Analysis Process

1. Evidence Preservation

  • Documentation of initial system state
  • Creation of forensic disk images
  • Preservation of logs and metadata
  • Chain of custody of evidence

2. Data Collection

  • Extraction of relevant data
  • System memory capture
  • Log and event collection
  • Configuration documentation

3. Evidence Analysis

  • Timestamp and metadata analysis
  • Event and activity correlation
  • Attack pattern identification
  • Timeline reconstruction

4. Documentation and Reporting

  • Detailed documentation of findings
  • Technical report creation
  • Evidence preparation for legal processes
  • Security improvement recommendations

Forensic Analysis Tools

Acquisition Tools

  • FTK Imager: Forensic image creation
  • dd: Command-line tool for disk copying
  • dc3dd: Enhanced version of dd with verification
  • Guymager: Graphical interface for acquisition

Analysis Tools

  • Autopsy: Forensic analysis platform
  • Volatility: RAM memory analysis
  • Sleuth Kit: File system analysis tools
  • Wireshark: Network traffic analysis

Recovery Tools

  • PhotoRec: File recovery
  • TestDisk: Partition recovery
  • R-Studio: Data recovery
  • Recuva: File recovery tool

Network Analysis Tools

  • NetworkMiner: Network traffic analysis
  • Xplico: Network protocol analysis
  • Chaosreader: Network session analysis
  • Tcpdump: Network packet capture

Analysis Methodologies

NIST Methodology

  • NIST SP 800-86 Guide
  • Four phases: Collection, examination, analysis, reporting
  • Focus on evidence preservation
  • Applicable to any type of incident

SANS Methodology

  • Six-phase process from SANS
  • Focus on memory analysis
  • Specialized SANS tools
  • Certified forensics training

ISO 27037 Methodology

  • International standard for digital forensics
  • Guidelines for identification, collection, and acquisition
  • Digital evidence preservation
  • Applicable to legal processes

Chain of Custody

  • Complete documentation of evidence handling
  • Data integrity preservation
  • Evidence access traceability
  • Compliance with legal requirements

Court Admissibility

  • Compliance with forensic standards
  • Process documentation used
  • Tool and method verification
  • Qualified expert testimony

Privacy and Confidentiality

  • Personal information protection
  • Privacy regulation compliance
  • Secure handling of sensitive data
  • Secure destruction of evidence

Forensic Analysis Benefits

Incident Investigation

  • Root cause identification of incidents
  • Compromise scope determination
  • Attack event reconstruction
  • Responsible party identification
  • Evidence collection for legal processes
  • Support for criminal investigations
  • Regulatory requirement compliance
  • Organizational interest protection

Security Improvement

  • Exploited vulnerability identification
  • Control improvement recommendations
  • Security measure effectiveness analysis
  • Future incident prevention

Forensic Analysis Challenges

Technical Complexity

  • System and technology diversity
  • Growing volume of digital data
  • Constant evolution of threats
  • Need for specialized tools
  • Local and international regulation compliance
  • Evidence preservation for legal use
  • Privacy and rights protection
  • Legal process admissibility

Resources and Time

  • Need for specialized personnel
  • Significant time for analysis
  • Tool and training costs
  • Time pressure in investigations

Best Practices

Preparation and Planning

  • Forensic procedure development
  • Personnel training involved
  • Tool and resource preparation
  • Coordination with legal teams

Professional Execution

  • Strict adherence to methodologies
  • Detailed documentation of all steps
  • Evidence integrity preservation
  • Responsible handling of sensitive information

Follow-up and Improvement

  • Process effectiveness analysis
  • Methodology updates according to evolution
  • Continuous personnel training
  • Tool and process improvement
  • Incident Response - Process that includes forensic analysis
  • Security Breaches - Incidents that require forensic analysis
  • Attack Vectors - Methods that forensic analysis investigates
  • Patient Zero - System that forensic analysis identifies
  • IOC - Indicators that forensic analysis correlates
  • APT - Threats that forensic analysis investigates
  • Chain of Custody - Process that preserves forensic evidence
  • Post-mortem - Analysis that includes forensic analysis
  • SIEM - System that collects data for forensic analysis
  • SOAR - Automation that can include forensic analysis
  • EDR - Tool that generates data for forensic analysis
  • CISO - Role that oversees forensic analysis