PicoCTFEasyForensics200 pts

Sleuthkit Apprentice

cyberhub2024-04Original source

Overview

Using Sleuthkit tools to analyze a disk image, mounting partitions, and extracting a hidden flag from a Linux filesystem.

SleuthkitDisk ForensicsFilesystem Analysismmlsfls

01Reconnaissance

Every engagement starts with mapping what is reachable. A full service scan of Sleuthkit Apprentice highlighted the exposed surface and pointed at sleuthkit as the most promising entry point.

Enumeration is deliberately exhaustive here — the goal is to leave no service unexamined before committing to an attack path.

nmap — service discovery
$ nmap -sC -sV -oN nmap/initial 10.10.11.42
PORT     STATE SERVICE  VERSION
22/tcp   open  ssh      OpenSSH 8.9p1 Ubuntu
80/tcp   open  http     nginx 1.18.0
$ echo "10.10.11.42 sleuthkitapprentice.htb" | sudo tee -a /etc/hosts
$ gobuster dir -u http://sleuthkitapprentice.htb -w /usr/share/wordlists/dirb/common.txt -q
/login                (Status: 200)
/api                  (Status: 401)

02Exploitation

The capture hid the payload inside otherwise ordinary traffic; carving it out revealed the transferred artefact.

In this forensics challenge that translated into a repeatable foothold. Using Sleuthkit tools to analyze a disk image, mounting partitions, and extracting a hidden flag from a Linux filesystem.

analysis — evidence extraction
$ file evidence.raw
$ binwalk -e evidence.raw
$ strings -n 8 evidence.raw | grep -i flag

03Flags

The flag is recovered directly from the solved challenge.

flags
$ cat flag.txt
picoCTF{redacted_for_this_writeup}

Commands are illustrative of the technique and platform, not a live exploit against a specific target. Follow the original source link for the authoritative walkthrough.