Evidence handling, transport, and storage form the critical continuum in computer and cyber forensics that maintains digital evidence integrity from seizure to analysis and presentation.
These procedures prevent alteration, loss, or contamination through standardized protocols, tamper-evident packaging, and secure environmental controls, ensuring chain of custody remains unbroken for legal admissibility.
Proper execution transforms fragile digital artifacts into reliable investigative assets, essential across all phases of modern cyber investigations.
Chain of Custody Fundamentals
Chain of custody documents every transition of evidence, establishing accountability and preventing challenges to authenticity.
Initial Handling and Packaging Procedures
Seizure sets the tone—immediate isolation preserves original state.
1. Power off devices safely after volatile capture; label cables/power cords attached.
2. Place in anti-static bags; seal in tamper-evident containers (bubble wrap for drives).
3. Separate power sources, avoid magnets; note operational state (on/off) and damage.
4. Inventory with photographs of scene, connections, and markings.
For mobiles: Airplane mode first; Faraday bags block signals.
Transportation Protocols
Secure transit minimizes risks during movement to labs.
1. Use locked, tracked vehicles; avoid extreme temperatures (ideal 10-25°C).
2. Chain of custody forms accompany sealed packages; dual personnel for high-value items.
3. International: Comply with customs declarations for electronics.
4. Emergency: Prioritize volatiles via encrypted remote transfer.
Never leave unattended; GPS trackers for high-risk shipments.
Long-Term Storage Standards
Secure repositories protect evidence through retention periods (often 1-7 years).
1. Climate-controlled vaults (50-60% humidity, 15-21°C); fire suppression without water.
2. Segregated access: Role-based locks, CCTV, badge systems.
3. Digital storage: Encrypted NAS/S3 with immutability (WORM policies), redundant backups.
4. Periodic integrity checks: Re-hash images annually.
Access and Release Procedures
Controlled retrieval maintains custody continuity.
1. Authorized personnel only; log entries/exits with purpose.
2. Working copies from originals; reseal promptly post-analysis.
3. Disposal: Secure wipe (DoD 5220.22-M) or destruction after retention.
4. Release to owners: Signed receipts, final hashes.
In practice, ransomware evidence undergoes vault storage post-imaging, with quarterly audits ensuring readiness for trials.
Common Pitfalls and Mitigation Measures
Procedural lapses compromise cases; vigilance prevents issues.
Training and automation (RFID tagging) enhance compliance in 2025 high-volume labs.
