Command Line Practice

Learn essential Linux commands through hands-on challenges.
Complete each level to unlock the next.

Available Levels
Level 1: Cyber Incident Investigation

Investigate a security breach on a Linux server. Navigate the filesystem, read log files, create directories for your investigation, and manage evidence files.

Commands
pwd ls cd cat mkdir rmdir touch cp mv rm
Level 2: Covert Communications Investigation

Analyze a suspect's workstation for hidden files and encrypted communications. Use advanced ls flags, identify disguised files, and decrypt secret messages.

New Commands
ls -a ls -l ls -R file gpg -c gpg -d
Level 3: Rogue Process Investigation

A production server has been compromised. Identify running processes, search for malicious activity, and terminate rogue processes before they cause more damage.

New Commands
ps ps -ef more grep grep -e kill kill -9 su
Level 4: Advanced Threat Hunting

An APT group has compromised the web server. Conduct a full investigation: map the attack, analyze evidence, identify all threats, and remediate the system. No hints provided.

Mastery Challenge
All Level 1-3 Commands
Level 5: Security Hardening & Audit Logging

Harden a compromised system by fixing file permissions and ownership. Set up audit logging with output redirection and secure sensitive configurations.

New Commands
chmod chown > >> < 2>
Level 6: Log Analysis & Forensic Data Mining

Analyze log files to understand a security incident. Extract, filter, and process text data to identify attack patterns and generate forensic reports.

New Commands
head tail wc sort uniq cut find
Level 7: Disaster Recovery & System Migration

Manage a server migration with proper backup procedures. Create and extract archives, monitor disk usage, and configure your environment for system administration tasks.

New Commands
tar df du echo env export history alias
Level 8: Ultimate Mastery Challenge

The final test of your Linux skills. A sophisticated attack requires you to use everything you've learned: navigation, analysis, processes, permissions, archiving, and more.

Ultimate Challenge
All Commands
student@cyberlab:~$ ls
documents/ downloads/