Introduction

Mobile devices often have strong security, including screen locks, PINs, patterns, biometrics, and full-disk encryption. Forensic investigators need to bypass these protections legally and safely to access crucial evidence.

⚙️ Common Security Mechanisms

1. Screen Locks

   • PINs, patterns, passwords, or biometrics (fingerprint, face recognition)

2. Full-Disk Encryption

   • Encrypts all data on the device; keys are often tied to the user’s passcode

3. Secure Boot & Sandboxing

   • Prevents unauthorized access to system files and app data

🔧 Techniques Used in Mobile Forensics

1. Logical Extraction

   • Uses official APIs or device backups to access data without breaking encryption

   • Pros: Safe, preserves evidence

   • Cons: Limited access; cannot recover deleted files

2. Physical Extraction

   • Directly reads raw data from the device memory

   • Often requires device to be rooted (Android) or using specialized tools for iOS

   • Pros: Full access, including deleted data

   • Cons: Risky; may alter data if not done correctly

3. Chip-Off & JTAG

   • Advanced hardware-level extraction

   • Involves removing memory chips and reading them directly

   • Pros: Bypasses OS locks

   • Cons: Requires high expertise, expensive, risk of device damage

4. Exploitation Tools

   • Tools like GrayKey, Cellebrite UFED, and Oxygen Forensics exploit vulnerabilities to bypass screen locks

   • These tools are updated constantly as OS updates patch vulnerabilities

5. Cloud & Backup Extraction

   • If the device is encrypted, investigators can sometimes access synced iCloud or Google backups

   • Provides access to messages, photos, app data without touching the physical device

🧪 Real-World Example

In a criminal investigation, a suspect’s iPhone was locked with a 6-digit passcode. Investigators used GrayKey to bypass the lock and extract encrypted iMessages and photos. Meanwhile, an Android device required rooting and Magnet AXIOM to extract WhatsApp chats and call logs.