Netcat: The Swiss Army Knife
Use nc for banners, file transfer, port forwarding, and simple reverse shells.
What is Netcat?
Netcat (nc) is a utility that reads and writes data across network connections using TCP or UDP. It is installed on nearly every Unix system and is invaluable for debugging, file transfer, and basic exploitation.
Basic Connection and Banner Grabbing
Connect to any TCP port to grab the service banner and manually interact with the protocol. This is the simplest form of recon.
# Connect to port 80
nc 192.168.1.100 80
GET / HTTP/1.0
[Enter twice]
# Connect to SMTP
nc mail.example.com 25
# Returns: 220 mail.example.com ESMTPAll lessons in this course
- Nmap Port Scanning Techniques
- Service and OS Fingerprinting
- Netcat: The Swiss Army Knife
- Network Enumeration Scripting