============================================ What You Need To Know About Ports ============================================ Author : Netw0rk Bug E-Mail : bug@netw0rk.freeserve.co.uk Date : March 98 ============================================ Well i think it is about time for another bug file, I have not had much time to write much but I thought i should tell you all about ports I recommand that you read through this at least once before trying to do anything One of the most important things about hacking is to find out as much as possible about the target. One good way to do this is to do a little port surfing, this can help you to see what os the server is running and what ports are open on which the server may be vulnerable A computer port is a place where information goes in or out of it. On your home computer, examples of ports are your monitor, which sends information out, your keyboard and mouse, which send information in, and your modem, which sends information both out and in. Now all of these ports are identified by numbers Your browser connects to port 80 when it loads a webpage! So hang on, lets take a look at some other common ports... Port Number Service Description ~~~~~~~~~~~ ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 7 echo Whatever you type in, the host repeats back to you 9 discard Dev/null -- how fast can you figure out this one? 11 systat Lots of info on users 13 daytime Time and date at computer's location 15 netstat Tremendous info on networks 19 chargen Pours out a stream of ASCII characters. Use ^C to stop. 21 ftp Transfers files 23 telnet Where you log in. 25 smpt Forge email from Bill.Gates@Microsoft.org. 37 time Time 39 rlp Resource location 43 whois Info on hosts and networks 53 domain Nameserver 70 gopher Out-of-date info hunter 79 finger Lots of info on users 80 http Web server 110 pop Incoming email 119 nntp Usenet news groups -- forge posts, cancels 139 netbios NETBIOS Session Service 443 shttp Another web server 512 biff Mail notification 513 rlogin Remote login who Remote who and uptime 514 shell Remote command, no password used! syslog Remote system logging 520 route Routing information protocol The idea behind port surfing is to pick out a target computer and explore it to see what ports are open and then later see what you can do with them You can get software that automatically scans for all open ports on a server i quote from the hackers handbook "1) You will learn something. Probing manually you get a gut feel for how the daemon running on that port behaves. It's the difference between watching an x-rated movie and (blush). 2) You can impress your friends. If you run a canned hacker tool like Satan your friends will look at you and say, "Big deal. I can run programs, too." They will immediately catch on to the dirty little secret of the hacker world. Most hacking exploits are just lamerz running programs they picked up from some BBS or ftp site. But if you enter commands keystroke by keystroke your friends will see you using your brain. And you can help them play with daemons, too, and give them a giant rush. 3) The truly elite hackers surf ports and play with daemons by hand because it is the only way to discover something new. There are only a few hundred hackers -- at most -- who discover new stuph. The rest just run canned exploits over and over and over again. Boring. But port surfing by hand is on the path to the pinnacle of hackerdom." Basically you pick a server and telnet to it Click on Terminal, then Preferences. In the preferences box you need to check "Local echo." You must do this, or else you won't be able to see everything that you get while port surfing.I also reccomend that you change the buffer size to about 3 or 4 hundred.However, be warned, in some situations everything you type in will be doubled. For example, if you type in hello the telnet screen may show you heh lelllo o. so lets see... telnet grande.nm.org 15 (in a shell account) or in windows... you can do this in a dos prompt or run c:\windows\telnet.exe I bet you are wondering what all that was!!! We have just telnetted to port 15 which is the network statistics port (netstat) which on some computers runs a daemon that tells anybody everything about the connections made by all the computers linked to the Internet through this computer. So from this we can learn that this server is a very important and busy one. Remember you can do most of this in win95 by running c:\windows\telnet.exe You just clickon connect, type in the server name and the port number Here's the basics of what to do: Get logged onto a shell account(or use telnet in win95). That's an account with your ISP that lets you give Unix commands. Or -- run Linux or some other kind of Unix on your PC and hook up to the Internet. Give the command "telnet " where is the internet address of the computer you wnat to visit and is whatever looks phun to you.