netcat

web 


HTTP HEAD REQUEST
telnet balaskas.gr 80
Trying 158.255.214.14...
Connected to balaskas.gr (158.255.214.14).
Escape character is '^]'.
HEAD / HTTP/1.1
HOST: balaskas.gr

HTTP/1.1 200 OK
Date: Wed, 15 Jul 2015 13:11:42 GMT
Server: Apache
Vary: Accept-Encoding,User-Agent
Content-Type: text/html; charset=UTF-8
Content-Language: el

$ nc -v ebalaskas.gr 80
GET / HTTP/1.1
HOST: ebalaskas.gr
[double enter]

port knocking/scanning 


nc -zv http://example.com 1-65355

telnet

web 


> telnet www.microsoft.com 80
set localecho
GET / HTTP/1.1
Host: www.microsoft.com
 
(enter twice)

mail 


> telnet mail.ebalaskas.gr 25
 
HELO ebalaskas.gr
MAIL FROM: ebalaskas@ebalaskas.gr
RCPT TO: ebalaskas@ebalaskas.gr
DATA
 test 
 this is a simple test
.


IMAP4 (TCP PORT 143)

> telnet ebalaskas.gr imap
1 LOGIN USER PASS
2 LIST "" *
3 STATUS "INBOX" (MESSAGES)
4 SELECT INBOX
5 FETCH 1 BODY[TEXT]
6 FETCH 1983 (BODY.PEEK[HEADER])
6 LOGOUT


POP3
> telnet ebalaskas.gr pop3
USER user
PASS pass
STAT
RETR 1
QUIT