For security audit, banner grabbing is one of the first activities to determine information about services on a remote computer. This article describe some very simple methods for command line banner grabbing without nmap.

telnet

# Example
$ telnet example.com 80
GET / HTTP/1.1
Host: example.com
[ENTER]

netcat

# Example
$ nc example.com 80
GET / HTTP/1.1
Host: example.com
[ENTER]

curl

# Example
$ curl -I example.com

“-I” for fetch only HTTP-header

wget

# example
$ wget -q -S example.com

“-q” for turn off Wget’s output. “-S” for print the headers