Challenge list
LinuxLevel 1★☆☆☆☆Linux-Environment Variable Basics. Checking Shell Startup Variables
One of the environment variables set when the shell starts holds the flag. Check it with the env command or echo…
LinuxLevel 1★☆☆☆☆Linux Basics - Permissions and SUID
Learn basic Linux commands and file permissions. Use hints to find SUID and retrieve the flag.
Web SecurityLevel 1★☆☆☆☆SQL Injection 101
This login form has an SQL Injection vulnerability. Log in as admin without proper credentials and retrieve the flag.
Web SecurityLevel 1★☆☆☆☆Web-04. The robots.txt Trap
Websites often serve a robots.txt file for crawlers. In this challenge, check whether a file that robots.txt tells…
Web SecurityLevel 1★☆☆☆☆Web-05. Directory Listing Trap
When an Nginx server has directory index listing (autoindex) enabled, anyone can browse the full file listing of a…
Web SecurityLevel 1★☆☆☆☆Web-06. Forging HTTP Headers
This application grants access based on the value of a specific HTTP header. Even values the browser never sends by…
Web SecurityLevel 1★☆☆☆☆Web-07. Tampering with URL Parameters
This web application checks the value of the GET parameter key on the server side. The required parameter name and…
Web SecurityLevel 1★☆☆☆☆Web-08. Tampering with POST Data
The login form contains a hidden input field that is invisible in the rendered page. Inspect it with developer tools…
Web SecurityLevel 1★☆☆☆☆Web-09. The Weak Basic Auth Trap
A protected area is guarded by HTTP Basic Authentication, but the developer accidentally left the credentials in an…
Web SecurityLevel 1★☆☆☆☆Web-10. Peeking Behind a Redirect
Accessing a certain page immediately redirects you elsewhere. Browsers automatically follow redirects, so think about…
Web SecurityLevel 1★☆☆☆☆XSS Basics - Guestbook
This web application has a basic XSS vulnerability. Find where input is reflected in the guestbook. The flag is at an…
CryptographyLevel 2★★☆☆☆AES-ECB Mode Weakness
ECB leaks repeated block patterns. This introductory task first checks the difference between encryption and encoding.…
ProgrammingLevel 2★★☆☆☆API Requests - Find the Highest-Profit Trade
When the container starts, a stock API begins running on http://localhost:9102 (you do not need to start server.py).…
Digital ForensicsLevel 2★★☆☆☆Find Attack in Apache Logs
Analyze the Apache access.log (common format) to find traces of SQL injection. Tell which attacks succeeded and which…
Digital ForensicsLevel 2★★☆☆☆Flag Hidden in Excel Macro
Analyze the macro code embedded in the Excel workbook and find the hidden authentication code (the flag). Learn how to…
LinuxLevel 2★★☆☆☆Linux-02. Privilege Escalation via a Sudo-Allowed Vim
Check which commands a regular user can run via sudo without a password. A well-known GTFOBins technique can let you…
LinuxLevel 2★★☆☆☆Linux-03. Reading Cron Configuration Files
This system has several cron configurations (/etc/cron.d, /etc/crontab, user crontabs, and more). Inspect each…
LinuxLevel 2★★☆☆☆Linux-Cron Privesc. Hijacking a Writable Root Script
Check the permissions of a cron script that root executes periodically. If a regular user can write to it, think about…
LinuxLevel 2★★☆☆☆Linux-Systemd. Checking a Service Unit's Environment Variable
A systemd unit file can set environment variables in its [Service] section. Inspect the registered service definition…
LinuxLevel 2★★☆☆☆Linux-Symlink Maze. Navigating a Branching Path
Several directories are connected in a tangled web of symbolic links. Without being misled by decoy hint files, follow…
LinuxLevel 2★★☆☆☆Linux-Script Debug. Fixing a Broken Bash Script
This script has several intentional bugs (typos, syntax mistakes) and fails to run to completion. Use bash's debugging…
LinuxLevel 2★★☆☆☆Linux-Network Basics. Connecting to a Listening Port
A background service on this system is listening on a specific port. Identify the port with ss/netstat and connect to…
LinuxLevel 2★★☆☆☆Linux-Backup Finder. Spotting the Real Temp File
The project directory contains several decoy backup/temp files ending in .bak, .tmp, or ~. The real flag is hidden…
LinuxLevel 2★★☆☆☆Linux-Pipeline. Narrowing Down Logs with grep and awk
The access log contains many entries. One IP address generated a burst of 404s, and stitching together the paths of…