Gone

MediumDigital Forensics

Overview

We have cloned a filesystem from a target device.  All the confidential data is redacted though.  Anyway, here's a copy of the filesystem. I'm confident there's nothing left to find. The data is gone... right?  Attachment:`challenge.zip` (contains `challenge.ext4`)  flag format : FLAG{}

Lab Details

Prerequisites & Requirements

  • Linux file systems: Particularly the ext4 file system architecture
  • Block allocation: How file systems allocate storage blocks to files
  • Slack space fundamentals: Understanding what happens to unused bytes within allocated blocks
  • Basic forensics concepts: Disk imaging and evidence preservation principles
  • Command-line proficiency: Comfortable working with Linux terminal tools
  • Access to a Linux environment (native or VM) since most forensics tools work best there

What Will You Learn?

  • Ext4 file system internals: Understanding inodes, block mappings, and metadata structures
  • Slack space forensics: A critical technique for recovering hidden or deleted data
  • Using debugfs: The ext2/3/4 debugging utility for filesystem analysis
  • Data recovery from raw blocks: Extracting bytes directly from disk images
  • Gzip decompression: Identifying and extracting compressed data streams

Tools

  • dumpe2fs: Inspect ext4 superblock and filesystem metadata
  • debugfs: Interactive debugger for ext2/3/4 filesystems
  • dd: Raw data extraction from specific offsets
  • grep: Pattern searching (including binary patterns)
  • hexdump: Viewing raw bytes in hexadecimal format
  • gzip / python3: Decompressing gzip-compressed data

Job Positions

Security Analyst

Tags

Ext4Slack SpaceData RecoveryFile CarvingDead Box Forensics