What you will learn
- Understand TCP/IP and common protocols
- Read packet and flow data
- Recognize suspicious network behavior
Network Security CTF Challenges
Learn TCP/IP, DNS, packet analysis, and network attack evidence through safe, reproducible exercises.
Network Security challenges
11 challenges available.
NetworkLevel 108. Network Basics - Learn Port Numbers
Networks use port numbers to identify services. For example, a web server (HTTP) usually uses port 80, and encrypted…
NetworkLevel 2Network Analysis - DNS Zone Transfer Leak
An unauthenticated DNS zone transfer (AXFR) against a misconfigured authoritative server was captured. Download the…
NetworkLevel 2Network Analysis - SMB Share Enumeration Leak
An attacker enumerating SMB shares on the network was captured. Download the packet capture (traffic.pcap), follow the…
NetworkLevel 2Network Analysis - Telnet Credentials
A legacy server was administered over Telnet in clear text. Download the packet capture (traffic.pcap), follow the…
NetworkLevel 2Network Analysis - Anonymous FTP Transfer
An anonymous FTP session was captured in clear text. Download the packet capture (traffic.pcap), follow the FTP data…
NetworkLevel 2Network Analysis - Clear-text HTTP Credentials
Analyze traffic intercepted on public Wi-Fi where someone logged in over plain HTTP. Download the packet capture…
NetworkLevel 3Network Analysis - SNMP Information Leak
A device speaking SNMPv2c with a weak community string (public) was captured returning a GetResponse. Download the…
NetworkLevel 3Network Analysis - SSL Strip Clear-text Credentials
An SSL Strip attack downgraded HTTPS to HTTP, so the victim's credentials traveled in clear text and were captured.…
NetworkLevel 3Network Analysis - Custom Protocol Decoding
Traffic from a system using a small custom binary protocol was captured. Download the packet capture (traffic.pcap),…
NetworkLevel 4Network Analysis - TCP Retransmission Covert Channel
capture.pcap contains TCP retransmissions with duplicate sequence numbers. Extract retransmissions whose payload…
NetworkLevel 5Network Analysis - IPv4 Overlapping Fragment Reassembly
The UDP datagram with IPv4 ID 0xbeef in fragments.pcap contains overlapping fragments that overwrite earlier bytes.…