Challenge list
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…
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…
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…
Linux-Package Info. Inspecting Installed Package Details
A custom-built deb package is installed on this system. Use dpkg or apt to inspect the package's details and find…
Linux-Process Hunting. Tracking Down a Running Process
Among several background processes, one has the flag embedded in its command-line arguments. List them with ps and…
Linux-User Investigation. Filtering the Target User with awk
Several users are registered on this system. Parse /etc/passwd with awk to find the one matching a specific condition,…
Linux-Log Rotation. Searching Compressed Historical Logs
Some older log files have been gzip-compressed by log rotation. Use a command that searches inside compressed files…
Linux-Log Explorer. Digging the Flag Out of Multiple Logs
Multiple application and system log files are provided. The flag is embedded in a single DEBUG-level line — narrow it…
Linux-Environment Secrets. Finding the Variable Named FLAG
Several environment variables, including some dummy credentials, are set on this system. List them with env and find…
Python Practice - Bulk Base64 Stream Decoding
Every line of data.txt (about 150 lines, created at every start) is Base64. Decode line by line; when the result…
Python Practice - Conditional CSV Sales Filtering
data.txt, created at every start, is a sales CSV (transaction_id,date,product_id,amount,status,ref,notes). Several…
Python Practice - Compound JSON User Query
Examine the JSON data.txt ({"users": [...]}) created at every start. Each user has id, name, email, role, active and…
Python Practice - Target-IP Access Log Tracing
data.txt (about 1,300 lines, created at every start) is a web server access log. Extract only the requests from…
Python Automation - Bulk Base64 Decoding
Every line of data.txt (about 150 lines, created at every start) is Base64. Decode line by line; when the result…
Python Automation - CSV Sales Filtering
data.txt, created at every start, is a sales CSV (transaction_id,date,product_id,amount,status,ref,notes). Several…
Python Automation - JSON User Query
Examine the JSON data.txt ({"users": [...]}) created at every start. Each user has id, name, email, role, active and…
Python Automation - Access Log Parsing
data.txt (about 1,300 lines, created at every start) is a web server access log. Extract only the requests from…
Python Automation - Password Hash Cracking
Examine data.txt (a list of SHA-256 digests) and wordlist.txt (800 four-character lowercase alphanumeric tokens), both…
Network Analysis - DNS Zone Transfer Leak
An unauthenticated DNS zone transfer (AXFR) against a misconfigured authoritative server was captured. Download the…
Network Analysis - ICMP Data Exfiltration
Data was exfiltrated from the internal host 10.20.0.15 to the external host 203.0.113.66 disguised as ping (ICMP echo…
Network Analysis - SMB Share Enumeration Leak
An attacker enumerating SMB shares on the network was captured. Download the packet capture (traffic.pcap), follow the…
Network Analysis - Telnet Credentials
A legacy server was administered over Telnet in clear text. Download the packet capture (traffic.pcap), follow the…
Network Analysis - Anonymous FTP Transfer
An anonymous FTP session was captured in clear text. Download the packet capture (traffic.pcap), follow the FTP data…
Network Analysis - Clear-text HTTP Credentials
Analyze traffic intercepted on public Wi-Fi where someone logged in over plain HTTP. Download the packet capture…