Only For Study Purpose DONT USE THE TUTORIAL  FOR iLLEGAL USES

The subject of this manual. Arguably synonymous to the term ‘cracking.’ Though some might tell you that
hacking means to creatively (and legally) explore different subjects of computers, like programming and

networking; while cracking refers to breaking into various systems. I’ll let you form your own definitions of each.
Virii :-
The plural of virus - meaning computer virus. Viruses really have nothing to do with hacking (contrary to
the movie ‘Hackers’) - but are a component of the underground. Originally, viruses were written in
assembly, which is like a very low-level programming language (the language used to write the
programming languages). Assembly code is just a step above binary (ones and zeros), and isn’t coherent at
all. At any rate, creating viruses then was honorable only because of the complexity involved. Now, though,
viruses are written in C, perl, C++, java, scripting languages (like javascript), and even ActiveX. Much less
skill is required - making virus writing not much of an accomplishment. In fact, programs like Virus Lab
exist that aid completely computer-stupid people in making their own viruses.
Types of viruses include: the boot sector virus. These infect (copy their code into) the boot sector of your
hard drive (the MBR, specifically), so the every time you boot up, the virus is loaded into memory. A virus
in memory is said to be ‘active’ - and once active, viruses can do whatever they were created to do. File
viruses are another kind. They infect executables (applications) or
individual files. Whenever the infected program is run, or the infected file loaded into memory (eg: opening
an infected MS Word file) the virus becomes active. Some less educated people may also tell you that a
Trojan Horse is another kind of virus - in fact most virus checker software look for them also. Trojans are in
fact, tools that we (hackers) use. They are back door programs, remote administration tools, fake login
screens, even keyloggers are considered Trojans by some. Don’t be confused though - Trojans are not virii.
I’ll go into more depth on Trojans later.
Crypto :-
Cryptography. Encryption is a security measure used in many ways. Put simply - encrypting something (a
file, a word, whatever) changes it into something incomprehensible. For example, if I encrypted the word:
‘windows’, it might look something like: ‘2mkd032nwds’. The text or file before encryption (’clear text’) is
converted into the jargon (’cipher text’) by means of an encryption algorithm. This is a complex
mathematical and logical equation used to cipher data. Two common uses of encryption are password
hashing and VPNs.
Whenever you log into any kind of computer system, the OS compares the password you entered to thepassword it has on file to determine if you entered the password correctly. However, keeping passwords onfile is inherently insecure. The solution - encryption. The system (be it UNIX, NT, or whatever) keeps thepasswords encrypted (called the ‘hash’), and decrypts in temporarily just long enough to see if it matcheswhat you entered. (This is all done in RAM, the password hashes in the actual password file on the harddisk stays encrypted).
Virtual Private Networks (VPNs) are two computers talking to each other over a publicly accessible
network (usually the Net) that encrypt all data before sending it to one another. The machine on the other
end of this link then decrypts it, and vice versa. This way, if the data is intercepted (by say, a sniffer - a tool
you’ll learn to use) it’s incomprehensible to the interceptor. This is the same way SSL (Secure Socket Layer
- encrypted HTTP or https) and SSH (Secure SHell - encrypted telnet sessions) work.
You can use encryption to your advantage. Get PGP (Pretty Good Privacy) or some other military-strength
encryption scheme and encrypt your secret files (ie: your hacker stuph!). Federal authorities cannot force
you - even in court - to give out the key to your encryption.
A little Hacker lingo
I’ll get the jargon out of the way now, in case I refer to one of these terms later.
OS - Operating System. The OS handles CPU and memory usage of the system, manages applications, and
provides the interface. Common OS’s are: Windows, UNIX, MacOS, VMS, DOS, Netware, OS/2, and Be.
Hacker - one who infiltrates and explores various computer systems for the sole purpose of expanding their
knowledge and satisfying their insatiable thirst for information.
Cracker - a hacker who acts maliciously. Deletes, crashes, implements viruses, etc.
Warez d00d - a lowlife techno weenie who sells pirated software (basically people who couldn’t quite make
it as a hacker).
Elite, leet, el33t, 31337, etc - a hacker who’s learned just about everything there is to know regarding
computers, networks, and security (not really possible). Many claim to be leet, very few are.
Newbie - an amateur hacker (different from a lamer).
Lamer - a complete hacker wannabe. The difference between a newbie and a lamer is this: a lamer knows a
little bit, decides that’s enough, and calls himself a hacker. A newbie also knows a little bit, but is humble
enough to know that there is a lot more to be learned.
Root - status on any system that gives the hacker total control of it. Usually, root is the desired end result of
any hack.
Shell - a shell is an interface between you as a user and a particular computer. Windows Explorer is a shell,
DOS prompts are a shell. If you log into a UNIX machine, you are using a shell
Rootshell - A rootshell is a shell with root (superuser) privileges to resources on that machine. You can
obtain a rootshell by either logging into the box as root (assuming you have the password) or by using an
exploit program to create a rootshell for you (more on this later).
Packet - when data is sent over a network, it is broken down into manageable chunks called packets. This
isn’t always the case, but in TCP/IP (the protocol used on the Internet), this is always true.
Protocol - a set of rules and guidelines that computers on a network must follow in order for
communications to be coordinated, and therefore successful. A protocol defines specifically how data is
broken into packets, sent over a wire, and reassembled at the other computer (and how sessions are set up
over a network).
Client - Usually refers to either A: a computer on a network that requests resources from a server, or a
computer that is not a server; or B: a program that makes request of a server or service. Netscape Navigator
and Internet Explorer are client software programs in that they request web pages from servers.
Server - Either A: a computer set up to share resources such as printers, files, or serve web sites, or B: a
program used to fofull requests, such as IIS (Microsoft’s Internet Information Server). More on clients and
servers later.
Proxy Server - Okay, if a company has its own network and its own website, there will be a portion of the
network accessible (with a username and password, of course) by anyone with Internet access. All the
HTML files for the company’s website will be somewhere on this segment of the network. Then, there will
be the portion of the network strictly for business purposes, hidden from the rest of the world. A proxy
server (along with sometimes a firewall) separates these two segments. So if you want to access the
restricted part of any network, you will need to do it via the proxy server. Also, if all the workstations in an
office have Internet access, they most likely do through the proxy server.
Firewall - Sort of like a proxy server, but has no other purpose but to keep unauthorized user out. Even if
you have a valid username and password for a system - if a firewall is in your way, you’re pretty much out
of luck. Hacking through one is very difficult -even for the leet. It is possible, though, and I’ve provided a
few techniques and angles to cracking them in the Firewall Penetration section.
Daemon - A daemon is a program that is active but does nothing until a certain condition becomes true
(similar to a TSR, or program in your Win9X system tray). Daemons often ‘listen’ on certain TCP ports of a
machine on the Net, and when a connection is made, they will do what intended. For example, when you
browse www.hotmail.com, you’re browser connects to TCP port 80, and the daemon listening on that port
(httpd, usually) sends you a copy of the web page you requested. More on this later.
Ethics
I won’t bore you with the usual “never use your powers for evil” stuph, but I have to throw out my opinion
on ethics. Hacking maliciously, be it by deleting files, screwing with configurations, or what have you,
besides being just plain mean, is a sure way to motivate people into tracing you. As a rule, you should never
change any files on a system you break into. The lone exception to this is altering log files to cover your
tracks (explained later). Hacking webpages - changing the default web page to ‘Pheer me! This box was
haxored by M4nt|S’ - is a bit of a gray area. Technically, its considered malicious, and will piss the
sysadmin of the network off. But if you must - at least back up the original index.html or default.htm file.
What you need - a Hacker’s equipment
Here is a basic list of the hardware, software, and other miscellaneous things you will need to begin your
days in the world of digital espionage.
· A computer (duh) with some kind of Internet access, be it PPP, a T1, or whatever (more on this later).
· One, preferably two accounts with an ISP, your phone company, or whatever. One should be in no way
shape of form attached to you (ie: someone else’s account!) More on this later.
· The following software:
An Internet browser.
A telnet client.
An FTP client.
A ping utility.
An IP scanner.
A port scanner.
A whois and nslookup utility.
A traceroute utility.
A password cracker.
Less necessary but very useful utilities include:
A CGI vulnerability scanner
A Net BIOS share scanner.
A finger client.
Compilers.
Cache rippers.
A brute force program of some sort.
Trojans, rootkits, and RAT’s.
Internet warfare tools.
Sniffers.
Keyloggers.
Sound complicated already? Its really not - I’ll explain the function of each, along with some good ones of
each. Almost all the programs I talk about here are available at The CyberUnderground
(http://home.cyberarmy.com/tcu). Otherwise, try www.hackersclub.com, www.hackers.com,
www.anticode.com, or just do a search online.
Internet Browsers
If you don’t know what this is or where to get one, you should probably put this manual away. IE and
Netscape are the two biggies. Lynx is phun to surf with on occasion (UNIX). Whatever browser you use,
make sure it allows for the use of proxies. IE and Netscape do (even the older versions), so now would be a
good time to familiarize yourself with the proxies options for each (more on this later). Also, make sure
your browser supports gopher (which is kinda like HTML but only text) incase you stumble upon an old
gopher server - these can be goldmines of information! IE and Netscape support gopher - to use it just type
gopher:// instead of http://.
Telnet Clients
Almost any OS you get these days has some sort of telnet client. Just type ‘telnet’ at a command prompt
(Windows or UNIX). This is the primary means in which you’ll connect to computers, and though its a
simple enough program, to hack you’ll have to become very familiar with how it works. Though fine for
newbies, you’ll probably find the Windows telnet client a bit… lackluster later in your hacking career.
PuTTY is a good replacement (which, by the way, supports SSL and raw TCP connections - very handy).
Whatever you use, make sure you can log (record) your sessions to a text file. The Windows client does
allow for this, so try it out.
FTP Clients
FTP is the Internet protocol used to transfer files between two computers, though I’ll go into more depth on
this later. Both UNIX and Windows 9X come with command-line FTP clients. IE and Netscape have builtin
FTP clients, and are even a GUI. The downside of them is that you can’t issue commands. To use it, just
type ftp:// instead of http://. You can also buy full-blown GUI FTP clients like WS FTP
(www.ipswitch.com), and FTP Explorer (www.microsoft.com). My personal opinion, though, is that
command-line is faster and gives you more control.
Ping Utilities
Both UNIX and Windows 9X have command-line ping utilities. Ping is a simple program (part of the ICMP
protocol - which you’ll learn later) with one purpose: to test the connectivity between two machines. To ping
a computer type:
%ping www.computername.com
(the ‘%’ is a UNIX prompt - similar to C:\)
If there is an unblocked path between you and www.computername.com, the ping will be returned by a
pong, a reply. Ping is used to test connections, and to determine the time it takes for the ping packet to make
a round trip. For example, a successful (unblocked) ping might look like:
c:\ping www.msn.com
pinging www.msn.com [221.54.64.7] with 32 bytes of data:
Reply from 221.54.64.7: bytes=32 time=100 ms TTL=32
Reply from 221.54.64.7: bytes=32 time=90 ms TTL=32
Reply from 221.54.64.7: bytes=32 time=95 ms TTL=32
Reply from 221.54.64.7: bytes=32 time=100 ms TTL=32
Whereas an unsuccessful ping might look like:
c:\ping 201.33.250.1
pinging 201.33.250.1 with 32 bytes of data:
unable to establish connection
You can play around with switches to send pings of different payloads (sizes), number of packets, and TTL.
With both UNIX and Windows pings, you can get an IP address from a host name, and vice versa. More on
IP addresses later.
IP Scanners
Sometimes called a subnet scanner. Ever heard of a wardialer? A wardialer is a program used by old-school
hackers. All it did was dial phone numbers in a specified range looking for modems. An IP scanner does the
same thing - enter a range of IP addresses or a subnet, and it will ping each address in that range or subnet
to determine if that address belongs to a computer (and if it is reachable, ie: not blocked by a firewall, proxy
server, or router). Most IP scanners prompt you for a start address and an end address - and it will attempt
to ping every address in between. Subnet scanners, though, ask for the first three octets, and it will scan
from .1 to .254 (the entire block). If you don’t know how IP addressing works, you will after reading the
TCP/IP section. Here’s an example IP scanner output screen:
Scan from: 130.11.8.1
Scan to: 130.11.8.10
——————————-
Scanning from 130.11.8.1 to 130.11.8.10
130.11.8.1: Connected
130.11.8.2: Connection Refused
130.11.8.3: Connection Refused
130.11.8.4: Connection Refused
130.11.8.5: Connection Refused
130.11.8.6: Connected
130.11.8.7: Connected
130.11.8.8: Connection Refused
130.11.8.9: Connected
130.11.8.9: Connection Refused
130.11.8.9: Connected
A ‘connected’ means that the machine can be pinged, or connected to. A ‘connection refused’ means that
either no computer belongs to that IP address, or that the machine isn’t accessible to you: behind a firewall
or proxy server. Some IP scanners show each machine in the scan, while others only show the ones that
were successfully connected to.
Good IP scanners are: HakTek, WS PingProPack, and Shadow Scan. Online scanners are available at places
such as http://infinityzone.cjb.net.
Port Scanners
A port scanner scans a particular IP address or hostname (a particular computer) for open ports. No, I don’t
mean serial or parallel ports. TCP ports - services, programs running on that server that can be connected to.
The concept of ports will be explained in detail in the TCP/IP section of this manual. For now, just know
that port and IP scanners are two very important tools you’ll need. Output from a port scanner might look
something like:
Scan: 20.1.139.21
Scan from: 1
Scan to: 1024
——————-
Scanning from TCP port 1 to port 1024
Open: 16 (chargen)
Open: 21 (ftp)
Open: 23 (telnet)
Open: 25 (smpt)
Open: 80 (www)
Open: 79 (finger)
This means that ports 16, 21, 23, 25, 79, and 80 are open an this particular machine (20.1.139.21). Port
numbers are generally used for a specific service, for example an open port 79 almost always is used for
fingerd (the finger daemon, or service).
Good port scanners are: NMap (UNIX), HakTek, WS PingProPack (which will scan IP ranges and ports on
each one), and YAPS. Online scanners are available also. These are nice because the server running the
scan scripts do the scanning, meaning their IP addresses get logged on the target machine - not your own.
This is a good way to keep from being traced.
Whois and NSLookup
Whois is a utility used to find out who a particular domain name (eg: hackersclub.com) belongs to. If you
whois a site, you’ll get the address, phone number, and email address of the technical contact (probably the
system administrator) and the administrative contact (probably the owner or person who runs that name /
business) of it. NSlookup, on the other hand, is a utility to find out what domain a particular hostname or IP
address belongs to, and what name servers represent it. This is useful when trying to map out networks, and
find determine all machines belonging to a certain domain. The concept of mapping networks, name
servers, and the like will be explained in more detail in later sections. Here is a sample whois query:
%whois aol.com
connecting to rs database…connected
America Online (AOL-DOM)
12100 Sunrise Valley Drive
Reston, Virginia 22091
USA
Domain Name: AOL.COM
Administrative Contact:
O’Donnel, David B pmdatropos@aol.com
(730) 453-4255
Technical Contact:
America Online trouble@aol.net
(730) 453-4160
Record last updated on 13-mar-97
Record created on 22-jun-95
Domain Servers listed in order:
dns-01.aol.com 152.163.12.1
dns-aol.fu.net 122.56.87.3
By whois-ing aol.com, we get a wealth of (public) info. We get phone numbers to social engineer if need be
(explained later). We get email addresses (valid login names). We get the hostnames and IP addresses of the
DNS servers (also explained later). All things to be noted when trying to hack a particular domain.
Here’s an example nslookup query:
%nslookup oliver.mail.tlsp.com
[no name] (oliver)
Hostname: oliver.mail.tlsp.com
Address: 103.222.54.8
System: SUN running SUNOS
nameserver: ns1.mail.tlsp.com
nameserver: ns.tlsp.com
nameserver: ns2.tlsp.com
nameserver: name.att.net
So, let’s say that we wanted some info on the computer oliver.mail.tlsp.com. We run an nslookup on it, as
shown above, and look at all the stuff we get. The IP address, what kind of machine it is (a Sun box), the
OS (SunOS - a flavor of UNIX). We get all the domain name servers for that domain - including tlsp.com’s
upstream provider - their ISP. All very useful information. If you’re new to hacking and aren’t sure how all
this info will help you break in, you will as you get further into this manual.
UNIX has whois and nslookup built right in - just type either at a prompt. Windows, however, doesn’t -
you’ll have to go and get nslookup and whois utilities for your Windows box. Good ones are Sam Spade and
WS_PingPrpPack - both available at TCU. What’s the difference between whois and nslookup? You whois
a domain name (something.com), whereas you nslookup a particular machine (IP address or host name).
Now would be a good time to download one of each (both programs listed above have both utilities) and
play with them a bit.
Traceroute
The Internet is an internetwork (hence the name), meaning a network of networks. These individual
networks are connected together by sophisticated pieces of hardware called routers. Oftentimes, there are
multiple routes between your computer and any other on the Net. Traceroute utilities do just that - trace the
route between you and any computer you specify, listing the IP address of any router it passes through to get
there. Traceroute is used to troubleshoot network problems, mostly. As a hacker you can do a number of
things with traceroute. If you’re being blocked from a particular IP address on the Net, you can run a
traceroute to it and find out exactly where you’re being blocked at. Also, you can find your target’s upstream
provider with traceroute - handy in mapping networks and
learning more about your potential victim. Both UNIX and Windows have traceroute utilities built in: for
UNIX, type ‘traceroute’, for Windows type ‘tracert’ at a command prompt. Output from a traceroute might
look like:
C:\tracert www.yahoo.com
tracing route to www.yahoo.com [250.217.111.6]
over a maximum of 30 hops:
1 150ms 144 ms 138 ms dialup-b.yourisp.net (110.135.87.4)
2 99 ms 145 ms 150 ms cisco7k.mr.com (32.55.87.1)
3 100 ms 144 ms 161 ms routel2.uswest.com (98.2.3.78)
4 160 ms 160 ms 143 ms gateway.con324.att.net (178.68.111.3)
5 147 ms 162 ms 177 ms intern.net3.yahoo.com (250.23.87.2)
6 171 ms 168 ms 165 ms www.yahoo.com (250.11.45.87)
trace complete
Here we had to go through 4 routers to get to www.yahoo.com. The first entry (dialup-b.byourisp.net) is
your computer - the last is your destination. Now, pretend for a minute that www.yahoo.com was blocked
by a firewall. Then your traceroute might look like:
C:\tracert www.yahoo.com
tracing route to www.yahoo.com [250.217.111.6]
over a maximum of 30 hops:
1 150ms 144 ms 138 ms dialup-b.yourisp.net (110.135.87.4)
2 99 ms 145 ms 150 ms cisco7k.mr.com (32.55.87.1)
3 100 ms 144 ms 161 ms routel2.uswest.com (98.2.3.78)
4 160 ms 160 ms 143 ms gateway.con324.att.net (178.68.111.3)
intern.net3.yahoo.com reports: host unreachable
Here intern.net3.yahoo.com is telling us that it wont let any our packets get past it. Most likely a firewall of
some sort. If ever you can’t connect to an IP address or hostname that you know to be valid, traceroute to it
and find out what’s blocking you. Now, if you look at all this hostname and IP address stuph and scratch
your head - don’t worry. You’ll understand better after reading the ‘TCP/IP and the Client/Server Model’
section.
CGI Vulnerability Scanners
CGI and how to exploit it is explained later in this text. Basically, these scanners look for CGI scripts on a
specified webserver that can be exploited. WebChk is a good one for Windows, as is Nessus, and SATAN
for UNIX. Online CGI scanners are sometimes found online, like at infinityzone.cjb.net.
Net BIOS Share scanner
A Share (as explained in the NT section) is a directory available to people on a network. Sharescanners just
scan an IP address range or subnet for these shares. This (like any kind of scanning) can be done manually,
but scanner software speeds the process up. WinHack Gold is a decent share scanner for UNIX, and Legion
is a good one for Windows
Finger Clients
Though fingering (explained later - sorry) can be done manually by telnetting into the finger port,
sometimes its useful to have a finger client too. UNIX has a built in client - just type ‘finger.’ Clients for
Windows include: WS PingProPack, WS Finger, and HakTek.
Compilers
Most exploits you find (little programs that exploit programming vulnerabilities in programs) are not
compiled, meaning in whatever programming language they were written in. You’ll probably want a perl
compiler, and an assembler. Most UNIX’s come with cc and gcc - handy C compilers. In fact, most of your
compiling will be done on a UNIX machine - either your own or a shell account. I promise - all this UNIX,
exploit, vulnerability, and programming stuph will make sense as you read further.
Cache Rippers
Cache rippers are programs that take passwords from memory of a machine. This doesn’t work on UNIX
and NT logon passwords. Rippers are good for looking ‘behind’ asterics of things like the Dial-Up
Networking dialogue box, and getting the passwords. These are useful only if at the machine, and are a
good way to filch ISP accounts. Download Dripper or Revelation and play with them a bit.
Brute Force Programs
Brute force is a simple attack that involves hurling passwords at a system until it cracks. A brute force
program might spit usernames and passwords at a UNIX login prompt, or at an NT login box. Many exist -
the problem is that BFing takes lots of time, and generally lets the admin of your target know that someone
is trying to get in. As explained later - BFing should be a last resort. Also, the type of BF engine you’ll use
depends on what exactly you’re trying to break into. For a generic BF program, download Claymore from
TCU’s Buffer Overflow section. Brutus (home.cyberarmy.com/tcu/buffer.html) is a good BF prog for telnet,
FTP, and HTTP also.
Trojans, rootkits, and RAT’s
Trojan’s were explained briefly in the Virii section above (due to the misconception that Trojans are virii).
Using Trojans will be explained later. They, rootkits, and RAT’s (Remote Administration Tools) are all
similar - they server as hidden backdoors, and utilities to remotely control other computers. Examples are
SubSeven, Back Orifice, and Netbus. Installing these on your target computer is usually the last step you’ll
take in hacking in. They allow you complete control of the system as well as a way back in later.
Internet Warfare Tools
These are programs with no other use that to wreak havoc. They come in a variety of categories. DoS
(Denial of Service) programs do nothing more than crash servers. Using these is usually as simple as
entering an IP address and hitting enter. bit** Slap and WinNuke are good examples of DoS progs. Using
these - besides being needlessly destructive - require absolutely no intelligence at all, and are usually used
by lame kiddies who couldn’t quite make it as real hackers. The only reason I even bring up Internet
Warfare tools is because its a good idea to have at least one on hand. Not WinNuke - programs like Divine
Intervention. DI ]|[ has utilities including ping floods, irc floods and bots, and the like. If you venture into
IRC channels, you may occasionally find yourself... "in a dark alley," and wouldn't want to be unarmed.
Keep Net Watcher up - if someone tries to nuke you - you'll know it.
Sniffers
Sniffers are a very useful tool for the seasoned hacker. In a nutshell, they 'sniff' all (or some designated)
packets that pass it on the network, and record all the data into logfiles for the hacker to view. Oftentimes
hackers sniff password hashes that traverse the network. How to use and place network sniffers will be gone
over later.
Keyloggers
Just that - programs that record keystrokes on a machine. Handy for stealing passwords. For example - lets
say you managed to hack into a Netware box with the account: Guest. But Guest has just about zero
privileges to anything phun. The answer might be to put a keylogger on that machine and see what turns up.
Specialized Tools
There are a few programs that are more specific in their purpose and use (and therefore more effective).
Here are the biggies that you should eventually have in your collection
SATAN and SAINT. SATAN (System Administrator's Tool for Analyzing Networks) is a UNIX based
exploit scanner. It looks at daemons bound to ports and queries for specific CGI files to determine possible
break-ins for you. Basically, you type the IP address of your victim, and it scans aggressively for known
vulnerability. Then, when it finds one, it prompts you with tutorials on how to exploit them. SAINT is an
updated version of SATAN. These programs are a must for serious hackers, and alone are enough to make
installing UNIX on your computer worth while.
Nmap. Network Mapper is also for the UNIX platform. It's a port scanner, but a very powerful one. Most
port scanners simply telnet to every port to see what's open, using the standard connect() system call. Nmap
is capable of a variety of scan types, including the half-open scan, the Xmas tree scan, and many others.
These types of scans don't telnet to ports. They exploit the way TCP/IP works to report the status of TCP
ports without making a full connection. This is handy for two reasons: one - you're IP address isn't logged
since you never made a full connection, and two - these kinds of scans will pass through some firewalls,
allowing you to scan protected computers. Nmap is not for newbies. You'll need to learn much about
TCP/IP (specifically, flags, such as SYN, ACK, and RST) to understand how Nmap works and how to use
it. But don't let this intimidate you. Install Nmap on your Linux partition and play with it a bit - you'll learn
valuable TCP info. Numerous Nmap text files explain how to use it, along with the manual that comes with
it. This is another must-have for elite hackers. Get it at www.insecure.org.
Nessus. This program is similar to SATAN, but for NT. A variety of plugins exist for Nessus, which keep it
updated on new exploits. When you scan a host with Nessus, it will tell you what ports and/or CGI scripts
are vulnerable, and will give you more info on these exploits. For more info on what exploits actually are,
and how to find and use them, wait for later sections of this manual.
Keeping from getting caught
Hacking is a gray area, as far as what exactly is legal, and what exactly isn't. Even if you follow the hacker code of ethics (never harm), you are still quite possibly braking one or more laws. Let me just say that if you are already on a system, with someone else's login name and password, you are blatantly breaking a few laws. Nuking is also illegal. IP and port scanning are not illegal, though they definitely cause suspicion. In
the past, measures to keep oneself safe included hacking from payphones, splicing your neighbor's line,
'bouncing' your call (explained later), and even using programs such as Modem Jammer. Now, you might
want to use one or more of these methods to keep from being physically traced (though modem jammers
don't work anymore), and another to keep from being traced over the Internet (to your ISP). The best and
probably easiest way to do this is use someone else's account, preferably on a different ISP. This is much
easier to do that one might expect. Shouldersurf someone typing in their login/password, do a little social
engineering (explained later), or even brute forcing to get a valid account. There are even programs out
there that if run on a machine used to access the Internet via a dial-up (with an ISP) it will give you the
password. One such example is Dripper (available at The CyberUnderground). As far as physically tracing
you goes, if you are using someone else's account you are sort of safe. If you have hacked into a system with
a low-level account (a 'guest' account, for example) and just got yourself root (see definition above), you
should seriously consider adding a few methods of security before reconnecting. To hack from a payphone,
get an acoustic coupler for your modem, set the receiver on it, and just dial out. Bouncing your call means
basically calling a modem somewhere that is designated as an 'outdial', meaning once connected, any
modem commands you issue will go to it, so you can dial from it somewhere else. If you are traced - it will
be to that modem. This can be defeated though, so its a good idea to bounce calls off a few outdials.
Outdials are pretty hard to find, but are most common on X.25's and other PSN's (for more info on outdials,
read any other hacking text, like "The Neophite's Guide to Hacking," or "The Newbie's Handbook."
Shell Account Bouncing
Anther security method (similar to bouncing your call) is bouncing your IP attack. Meaning - telnet to
system that supports telnet itself (usually UNIX) - then telnet to your target. Finding and obtaining access to
one of these is difficult for a new hacker, so I'll go into greater detail on this later.
Wingates
Another effective method to having your IP address logged into the system you're connected to (and thereby
"busted,") is bouncing your packets off a WinGate host. WinGate is a server software program that acts
kind of like a proxy server and firewall all in one (see above for definitions). As with a generic proxy
server, all computers in the office that the WinGate computer is in connect to it to get to the Internet - and
you can do the same. All you need is the IP address or domain name of a WinGate host. Telnet to it, and
type the IP address you want to get to at the prompt you get. The IP address of the WinGate box will be
logged as you connect - not your own. What's even better is that Wingate's don't log (keep track of) who
connects to them. Unless, of course, the sysadmin uses some third-party software to monitor network traffic.
Finding WinGates is very easy - just go to any hacker website (www.cyberarmy.com is a good one) and
look at their database of WinGate's. You'll have to weed through lists of bad WinGate's though, so you may
be better off getting a WinGate scanner and doing it yourself. If you're really smart, you'll bounce your
packets off a few WinGate's before getting to your target.
Proxies and Anonymizers
If someone is 'using proxies' to be stealthy, he is simply connecting to web pages (and possibly FTP,
Gopher, etc) through a proxy server. Check the description in 'A Little Hacker Lingo.' Publicly accessible
proxies (or proxies that the owner doesn't realize are accessible by the world) can be connected to and made
proxy all requests. Meaning if you use proxy1.ozemail.com.au as your proxy server, then surf over to
www.yourtarget.com - you don't directly connect to yourtarget.com. Instead, you connect to
proxy1.ozemail.com.au, inform it that you want to surf yourtarget.com, and it fetches you that html file. The
proxy's IP address is logged on your target during the connection, since it was the one who actually
connected to it, and not your own.
CGI Anonymizers are nothing more than proxy servers as well. Www.cyberarmy.com has an anonymizer
for you to surf anonymously with. Also, if you use these URLs:
http://proxy-mail/mailcity.lycos.co...tor.cgi?http://
You can use Mailcity's proxy server to surf anonymously. (These are the proxies used when you click a link
while at Mailcity.) Non-CGI proxies must be entered in your Internet connection settings (of IE or
Netscape).
Filched ISP Accounts
The best way to hide your identity, though, is with a stolen account. Use Dripper or some other Cache
Ripper to get the Dial-Up Networking password from someone you don't like. Or, sign up for some free ISP
service (NetZero, Altavisa Free Access, or WorldSpy) and give fake account information to get an account
that's not attached to you. Make sure that you're using proxies when you sign up, or they'll know who you
are when you sign up.
Covering Your Tracks
Remember: all computers keep logs of activity. Once you break in, open the logfiles and delete any entries
that involve you (especially ones that logged your IP address). In UNIX systems, look for logs in /var or
/var/adm. In NT, look in \winnt\logs or \winnt\system32\logfiles or in a directory of a particular service (eg:
HTTP or FTP). Program also exist that will cover your tracks in logs, such as cloak.c for UNIX (available
at TCU).
As a rule of thumb, the amount of security you should be using is directly related to the seriousness of your
hack. Though, you could be breaking many federal and state laws without even being close to having root
access, and not even quite sure what you are doing. Always be at least a little paranoid: you'll last longer in
the h/p world. It cannot be stressed enough: be as safe as possible.
TCP/IP and the Client/Server model
If by this point you're completely lost, you might want to read some other basic computer stuph before
venturing on here. If not, roll up your sleeves: you're about to learn the very heart and soul of the Internet
and Hacking today.
TCP/IP
Transfer Control Protocol/Internetwork Protocol. The 'language,' or means for which packets are exchanged
over the Internet, or any intranet. TCP/IP is a set of rules and regulations that specifically define exactly
how data is transferred between computers on a network. TCP is the upper-level protocols (explained
shortly) like Telnet and FTP. IP is the lower-level protocol, used for routing data over a network. Hence the
term 'IP Address.' TCP/IP has several sub-protocols, known as the TCP/IP protocol suite. To utilize any of
these subprotocols, you just need a client of that. For example, Windows 95 and above has a built-in FTP
and Telnet client (a client, when referring to a protocol, is a program that lets a user utilize that protocol). In
this section I will explain each of these subprotocols, and other protocols used over the internet.
Client/Server
One concept that it is imperative you understand is the Client/Server model. Every protocol is utilized with
software. For example: HTTP (Hyper Text Transfer Protocol, the protocol used to transfer HTML web
pages to and from your computer [this is why it is at the beginning of URL's you visit] ). This protocol is
put to use by software. This software has two pieces, a client side and a server side. When you type in a
URL or click on a link, you are using a HTTP client software program (a browser) to request a copy of a
particular web page. Then, the server of the URL you requested has HTTP server software, that receives the
request (in the form of data packets), and provides you with a copy of it, by sending it back to your
computer. A server side software package is also called a service or daemon, and is accessed via TCP ports.
A port is a “virtual channel” used to transfer packets of a specific protocol between a client and a server.
When you hear the term ‘portscanning,’ what is being referred to is the scanning for protocol, or services.
Also, each port (service installed on the server in question) has a number assigned to it (eg: telnet is
generally number 23). At any rate, think of client side software as the requestor, and the server side software
as the provider. Any time you make a connection with a machine on the web (with Telnet, Internet Explorer,
or whatever), your client is talking to that server via a common protocol.
TCP Subprotocols, and other Protocols
PPP
There are many protocols, most of which discussed here are used over the Internet’s high-speed digital lines.
However, there are lots of protocols used over regular analog phone lines, used before the Internet was a
major computing tool. These include Kermit, Xmodem, Ymodem, etc, and all have parallels in the TCP/IP
protocol suite. However, the only “analog phone line” one I’ll cover is PPP. PPP (Point to Point Protocol) is
the protocol used to connect to your ISP’s server, who intern sends and receives TCP/IP packets over the
internet for you. SLIP is similar, but not as effective or as widely used. Basically, the way you are able to
communicate with the digital network of the Internet is that your ISP translates TCP/IP packets to PPP
(actually encapsulates) so they can travel over phone lines, and vice versa.
Telnet
Let’s start at the basics - on, say, a UNIX platform, there is one or more UNIX boxes - the computer that
does the processing and holds all the data (files, applications, the OS, etc) which is the computer on the
network that you are most likely trying to hack into. Then there are a slew of dumb terminals directly
connected to it. A dumb terminal consists of nothing more than a monitor and a keyboard - everything a
user types/does on a dumb terminal is handled by the UNIX box. Now, telnet is a protocol/application that
allows people to connect to a computer remotely (over a phone line or the Internet) and process data locally
- meaning when you connect to a UNIX box via telnet, it just as if you were at a dumb terminal directly
connected to the UNIX box. Telnet is the protocol you will be using to access the computer you are hacking
into. You can also telnet to a port other than 23. Most client / server protocols send data back and forth with
various commands defined in that protocol. You can telnet to a port and issue these commands by hand, and
the daemon will send commands back to you thinking you’re a client. For example, when you type this in on
your browser:
http://home.cyberarmy.com/tcu/underground.html
your browser connects to port 80 (HTTP, the port used for transferring of web pages) of
home.cyberarmy.com and sends this command:
GET /tcu/underground.html
in order to view that web page. You can telnet to port 80, issue the same command, and you’ll get the html
file sent to your telnet client (just as it would be sent to your HTTP client, your browser). Kool, eh?
FTP
File Transfer Protocol. This is the protocol used to transfer files between computers over the Internet.
Whether you are downloading password files or uploading changes to their HTML files, you will do it
through FTP. To start an FTP session, you need to log in to the service with an FTP client, just as you
would with Telnet. More on this later. Incidentally, the later browsers from Netscape and Microsoft have an
FTP client built in. To use it, type ‘ftp’ instead of ‘http’ in your browser. FTP has more commands than just
to send and receive. Type ‘help’ to get help from your client, or ‘remotehelp’ to ask the server for what
commands it accepts. Also, if you telnet to an FTP port, you can log in, but without the right client that
understands the FTP ‘language,’ you won’t be able to transfer files.
SMTP
Simple Mail Transfer Protocol. This is the protocol used to send and receive email. If you connect to a
SMTP port (by telnetting into it) you can issue SMTP commands. When you send an email, along with the
actual letter go along its protocol. This means that the SMTP packets (made up of your letter and other
protocol-specific data) connects to port 25, and issues the appropriate commands to the SMTP service in
order for the letter to reach its recipient. You can also connect to this port and issue these commands
manually. The use of this could be sending email and changing the sender address to someone else (possibly
the recipients employer). Also, with the VRFY command, you can find out whether or not a particular
account (login name) exists on the network in question. Actually, you can telnet to port 25 of a machine and
actually send someone email. Just enter the commands that an email client would - use the HELP command
to familiarize yourself with the various SMTP commands.
HTTP
Hyper Text Transfer Protocol. This, again, is the protocol used to transfer HTML pages back and forth
between two computers. If you see an open port 80 (www), this machine has a web site. SSL is the
encrypted version of this - see the Crypto section above for more about SSL.
Finger
This protocol (also a UNIX utility) is used to obtain information about users on a remote machine. With a
finger client, you can see who’s logged on currently, and can find specific information about a specific user.
Having finger on a UNIX machine is a very bad idea. Anyone with a finger client (or anyone who wants to
telnet into the finger port) can find out who’s logged in, get a list of users for that computer, and get info on
specific users. If your client can’t talk to the daemon, telnet in, and hit enter once or twice. Try typing ‘@’ or
‘finger’ or something similar to get a response. Then, type in usernames that you find and hit enter. All this
valuable info, without ever logging in - very useful to the hacker. If ever you find an open finger port, use it.
It could just be the point of entry you were looking for.
DNS
Domain Name Service. If a computer has this port open, it generally means that this particular computer is a
domain server of that network (the spokesperson, if you will). These computers act as the spokesman for
that particular domain. They hold the DNS table, which translate hostnames into IP addresses, so when you
connect to www.someserver.com, it knows what IP address you’re talking about.
NBT
This stands for Net BIOS over TCP/IP, and is what Windows networks use. Another name for this is
‘nbsession,’ (Net BIOS Session Service) which generally indicates Net BIOS used over a Wide Area
Network (such as the Internet), being that Net BIOS by itself (without TCP/IP) cannot be used over a
WAN. This protocol is used in conjunction with ports 135 and 139. The clients for these ports is the Client
for Microsoft Networks. You’ll learn how to use it in the NT section.
SNMP
Simple Network Management Protocol. Used to diagnose and manage networks. Utilities like ‘netstat’ for
UNIX use this lightweight protocol. Certain NT applications of SNMP are vulnerable - check your local
exploit archive for more info.
NCP
Netware Core Protocol. Just that. This isn’t a TCP/IP subprotocol. Actually, its usually used in conjunction
with SPX/IPX (Sequential Packet Exchange, Internetwork Packet Exchange), Novell’s routable protocol.
Net BIOS
This protocol is a very lightweight one, used for smaller LANs. Its not routable (meaning by itself, cannot
be used to connect networks, or used on the Internet), primarily because network addresses are nothing
more than computer names. Windows networking relies largely on Net BIOS, but its also used with OS’s
such as UNIX sometimes.
NetBEUI
Microsoft’s NetBEUI (Net BIOS Extended User Interface) is what you’re using when you browse your
network neighborhood. NetBEUI uses UNC’s (Uniform Name Convention) to locate resources. A UNC
looks like: \\computername\sharename\path. With this format - you can access any data on your NetBEUI
(or TCP/IP - if it’s a Windows network) network. More on this later.
UDP
UDP - Uniform Datagram Protocol. This protocol is actually used in place of TCP for some applications.
TFTP, for example, uses UDP. So does SNMP. UDP encompasses many subprotocols, just like TCP does -
so its not actually a TCP subprotocol either. Some network utilities you’ll use will actually use UDP (UDP
over IP, as opposed to TCP over IP), but the difference is transparent. Get yourself a networking book for
more on these kinds of things.
POP3 and IMAP
These are used for email. POP3 (Post Office Protocol version 3)stores and retrieves mail on a server. IMAP
requests them - in some cases. For example: when you use Outlook Express to download your email, you’re
getting it from a server with POP3 on it. If you use a web-based email provider such as Hotmail or Mailcity,
you view and manipulate it with IMAP.
SSH and SSL
SSH (Secure Shell) is basically just encrypted telnet sessions. SSL (Secure Socket Layer) is encrypted
HTTP. To use SSL with IE or Netscape, type https:// instead of http://.
AppleTalk and AppleShare
These are not TCP subprotocols. They are used by Mac networks, but can be implemented over IP (to
connect to the Net). The ‘Miscellaneous OS’s’ section goes over this a little.
These, along with many other protocols are used regularly over the internet as well. It is not in the scope of
this text to explain them all, so I encourage you to research them and the others I’ve covered in more detail.
I could cover pages and pages of TCP/IP stuph. As you gain a bit of experience in this craft, you will need
to learn more about this. For now, just understand that when you do anything on the Net, whatever program
you’re using sends packets in the appropriate command form (TCP/IP commands) across the cable
connections that make up the Internet. And of course, TCP/IP conforms to the OSI model - the backbone of
every network protocol, the way everything communicates digitally. Go out and read about OSI - you’ll
appreciate it later.
Getting Started - Your first night as a Newbie
Okay - you’ve found the network/system that you want to hack. What’s first? Find out which of these
protocols the target supports. Can you telnet to this computer? Can you FTP to it and copy files from it? To
find out, you will need to run a portscan on it, with you portscanning utility. Just type in the URL or IP
address of the machine in question, and start scanning. You will be shown what protocols (TCP/IP
subprotocols and others) the target has. It will not, however, tell you that it supports TCP/IP, because, to put
it simply, it has to have TCP/IP to be on the Internet. What you are looking for here is services - these
TCP/IP subprotocols and other services/ports. Do not let the term port mislead you - we’re not talking about
physical ports. If you don’t understand this first step, reread the TCP/IP section.
Now, if the portscan indicated that the target machine supports telnet (port 23), you can telnet to it, and
attempt to log in. Go ahead - try it. You’ll need a valid username/password combo to get it, which we’ll get
to later.
If port 21 is open, that means that the machine supports FTP, and files can be transferred back and forth
from it. But, like access via telnet, you’ll need a login name and password. A default “anonymous” account
is ftp/ftp for a username/password, so go ahead and try that. If this works (and don’t be surprised if it
doesn’t), you won’t have much in the way of access privileges (meaning you’ll be able to look at files, but
usually not copy files to your computer, and most likely not copy files to it). If you can anonymously log on,
you at least have your foot in the door, and can possibly use this as a stair stepping to get further into the
system. More on this later. Once logged on via an FTP port, commands to jump around from directory to
directory and copy files is very DOS-like (actually more UNIX-like than DOS, but if you know a little
DOS, you should feel comfortable navigating the system). Type ‘help’ or ‘?’ for a list of commands. When
you do this, you are accessing a help file on your computer. To access the help file on the computer your on
(which is usually more extensive and has commands specific to the computer your logged on to) type ‘rhelp’
or ‘remotehelp,’ or something similar. Or you could telnet to the FTP port and type ‘help.’ FTP is the only
way to transfer files between the target computer and yours - which you will need to do to get password
files, change their website (’this site has been hacked by Kurruppt2k’), upload exploits, or whatever. More
on this later. One last note on FTP - you can telnet to an FTP port, and log in. However, since you are not
using an FTP client, you will not be able to do much once inside (like get directory listings or download
files) because your telnet program does not follow the rules and guidelines (protocol) specified in FTP.
Again, you can telnet to any port, but if the right commands are not issued (usually done by your client
program), you may not get anywhere, and may even be disconnected. Telnetting to ports that you aren’t sure
what are, though, is a very good way to learn about the computer you are targeting, and is usually necessary
to break in.
Now, if your portscan turned up either ‘www’ or ‘http,’ that means that you’ve found the computer that has all
the HTML files (website files) that contain this organizations website. This really is only relevant if you are
attempting to break into the target’s website. To do so, you’ll need access to the index.html or default.htm
file (usually only accessible to superusers, or root accounts), and will have to FTP the page you will replace
theirs with, and replace index.html with your own. Doing this, though, could be considered cracker-like, and
slightly malicious. This also tends to piss sysadmins off, and may drive them to attempting to find you - so
be careful!
A last few notes on TCP/IP. You need to understand the structure of a URL, and of an IP address. Every
computer on the Internet is designated by an address. The addressing scheme (IPv4) looks something like
this: 38.233.203.2. Generally, the very last number is the node address, or the computer’s address. The rest
is usually considered the network address (depending on the Class - read a document on IP addressing for
more info). Each number between the decimals (called an octet) can be from 1 to 254. So the IP address is
in the 38.233.203 subnet. The last number, again, specifies the computer in that subnet. So if you wanted to
see what other machines were on that subnet, you would scan from 38.233.203.0 to 38.233.203.254. Now,
each IP address can also have a name. If 38.233.203.2 belongs to the netscape.com domain, it might be
www.netscape.com, or mail.netscape.com, or something similar. So when you type www.netscape.com to
visit its website, you could also type http://38.233.203.2 (assuming that was its IP address). Which brings us
to the URL. Here is a typical “web address”: http://www.microsoft.com/servives/windowsNT. The http://
specifies the protocol used. You could also replace it with ftp:// or even telnet://. (Note: to log in via ftp
with your browser, use ftp://usernameassword@www.yourtarget.com.) The www.microsoft.com is just the
computer name. The DNS protocol handles resolving the name into an IP address. The
/services/windowsNT is the path to the file you are requesting (index.html or default.htm, if none other is
specified), just like a path on your computer (with foreword slashed instead of backslashes).
Webservers usually have what’s called a wwwroot directory. This is the root of the browsable machine.
Meaning the path on the machine itself:
/texts/wwwroot/images/source.gif
of the computer www.gateway.com is:
http://www.gateway.com/images/source.gif
This is important. The root to you, the browser of a webserver, isn’t the actual root of the system’s hierarchy.
Why? So people browsing can’t access the entire machine - just the web pages and stuff that the webmaster
wants you to see. So lets say you cracked a UNIX machine with a non-root account, and wanted to
download the password file of the Gateway computer above. The file is (in this case) /etc/passwd. To
download it, you’d copy it to /texts/wwwroot. So its actual path is /texts/wwwroot/passwd. But its URL (to
anyone browsing the server) would be www.gateway.com/passwd. So you’d just type that into your browser
to download the password file, and you’re off to cracking it. Of course, doing this without proxies or a
stolen ISP account will get you traced and busted right away.
You’re First Hack
Okay, you now should have enough preliminary knowledge to start your very first hack. Pick a target.
Universities usually have somewhat lax security. Pick something relatively easy for your first time. Stay
away from government networks and those belonging to large businesses and corporations. The very first
step is finding the domain name of your target. If your target is www.spicegirls.com, the domain name is
simply spicegirls.com.
Step one - Intelligence Gathering
Every successful hack starts with a little preliminary investigation. The more information you have about a
specific domain, the better armed you are. Open a notebook and start an “info collection” of your target.
First, visit their website. Try to view every page, and write down anything of importance. Copy down all
email addresses - as these are also usually valid login names. Write down anything else of relevance. Look
at the source HTML and see if there are links to other computers you didn’t know about. Next run a whois
and nslookup on the domain, with your appropriate utility (available at The CyberUnderground). This will
give you very useful information. You’ll get the domain’s nameservers, the administrator, and a few more
email addresses, other computers on the network, and other useful stuff. Copy everything down. Another
trick is sending an email to the domain with a username that you know doesn’t exist (eg:
blablabla@yourtarget.com). The SMTP service of whatever server is designated as the primary mail server
of that network will return a letter to you saying that there is no such user. In the header of this email will
also be some useful information - copy it all down.
Step two - Network Scanning
Next you should try to get a scope of what kinds of computers are on the outside of this network (by
outside, I mean what machines are “on the Internet,” and not behind a firewall or proxy server). To do so,
you will scan the subnet with your trusty IP scanner. Again, a subnet is every computer (numbers 1 through
254) on a particular range of IP addresses. For example, 253.87.8.3 and 253.87.8.45 would be on the same
subnet, whereas 253.87.8.45 and 253.87.11.12 are not. (Actually, class C subnets are often-times broken up
even further - read an RFC on IP to learn all about IP addressing, packet structure, etc.) To scan the subnet
of your target, do as follows. Ping the hostname (your computer should have a ping utility, as do most of the
hacker programs you should already have). This will give you the IP address. If the IP address is
253.87.8.45, scan the entire subnet, which would be 253.87.8.1 through 253.87.8.254. This will tell you
every computer on that subnet - their IP address’s and hostnames if applicable. If you already know of two
computers on different subnets, scan both. Now, write down each computer you found and their IP
addresses, along with any relevant notes. When you’re done, you should have a list of each (or most) of the
servers on your target’s network, not behind a firewall/proxy server, and accessible to you.
Step Three - Point-of-Entry Determination
Now that you know what servers are on this network, you need to find out what kinds of computers they are:
what OS’s they are, and what services are running on each. So what do you do next? You guessed it - you’ll
scan for services, or ports, on each computer you found. Use your portscanner and scan each computer you
wrote down. Think of each service running on a machine is like a door that you might be able to break in
through. Below I’ll explain methods to use to possibly “break and enter” through each “door.” Now, to get
in, and have the power to actually do things and explore the network, you’ll need to telnet or NetBEUI into
one of the machines. This is usually the last step of hacking your way in, and you’ll need a username and
password to do so (or an exploit, which will be explained shortly). You’ll hack into other ports in order to
get these usernames and passwords. Now, a username and password that works on one machine of the
network will usually work on all on that same network, so if you get passwords from one computer, you can
use them on a different one to get in. Also, if there are no telnet ports, you can still (sometimes) log in via
FTP. You won’t be able to do much (like run any programs on the computer), but you will be able to look
around and upload or download files from the computer. What steps to take here entirely depend on the
Operating System of your target. Some networks you’ll find will have a variety of OS’s, some will have just
one. Here is a list of ways to fingerprint computers - find out what their OS is.
Server Fingerprinting
· If port 23 is open, its probably UNIX. Telnet to it to find what flavor (BSD, Solaris, etc). It is important!
· If port 135 or 139 is open its probably NT. At a DOS command prompt, type:
c:\nbtstat -A [ip address]
If you get a response other than ‘host not found,’ it’s definitely NT (or possibly Windows 9X).
More on what this nbtstat stuff means in the NT section.
· If none of the other ports are open, try telnetting (or FTP-ing) into port 23, and give the command:
ftp>SYST
Without the prompt (just ’syst’). This might tell you the OS of the machine, or at least if it’s UNIX
or NT. Sometimes you have to log in before giving this command, sometimes not.
· If port 80 is open you can telnet in and issue this command:
GET / HTTP/1.0
To find out the webserver running. You’ll probably want to turn on your telnet logging, because
the info will fly by your screen really fast. If the webserver is IIS - the machine is NT. If the webserver is
Apache - the machine is UNIX (probably Linux). Otherwise, look up whatever
webserver is running to find out what OS its for.
· If ports 21, 23, 80, 135, and 139 are all closed, there’s no easy way to find the OS. But then, without at
least one of these ports being open, you probably won’t be able to hack in either (these ports are the primary
means you’ll get in) so pick a different computer to try and break into.
The Kinds of OS’s you’ll run into are pretty much just NT Server (along with an occasional NT Workstation
and Windows 9X box), and UNIX. At least once in a while, though, you’ll run into a Netware box, and even
a mainframe wired to your target’s network. That means to become elite, you’ll have to learn a handful of
operating systems.