How to Hack

Hacking can be difficult and there are many different ways to hack and many different exploits to use. Hacking is neither defined nor limited by exploitation or exploration. Hacking into someone else's system may be illegal, so don't do it unless you are sure you have permission from the owner of the system you are trying to hack.

Hacking was primarily used for learning new things about systems and computing in general, 'in the good ol' days'. In recent years it has taken dark connotations and in general has been looked down upon. Likewise, many corporations now employ "hackers" to test the strengths and weaknesses of their own systems. These hackers know when to stop, and it is the positive trust they have built that earn them large salaries.

There is a major difference between a hacker and a cracker. A cracker is motivated by malicious reasons; a hacker is attempting to gain knowledge through exploration.
Learn a programming language. C++ is very useful, although difficult to learn. Python is much easier to learn, although less flexible. In order to break into web systems, learning server side languages such as PHP will help you immensely. Perl is also a very useful language to learn, as it can be used in many situations, and once you are familiar with the syntax (which is similar to that of C), you will be able to create Perl scripts very quickly.
Use a *nix terminal for commands. Cygwin will help emulate this for Windows users. DOS is more limiting than a *nix terminal. The tools in this article can be found for Windows based machines. Nmap particularly, uses WinPCap to run on Windows and does not require Cygwin. However, Nmap works poorly on Windows systems due to the lack of raw sockets. You should also consider using Linux or BSD, which are both more flexible, more reliable, and more secure. Most Linux distributions come with many useful tools pre-installed.
Try securing your machine first. Make sure you fully understood all common techniques, including the way to protect yourself.
Know your target. The process of gathering information about your target is known as 'enumeration'. Can you reach the remote system? You can use the ping utility (which is included in most operating systems) to see if the target is 'alive', however, you can not always trust the results of the ping utility, as it relies on the ICMP protocol, which can be easily shut off by paranoid system administrators.
Determine the operating system (OS). This is important because how can you gain access to a system if you don't know what the system is? This step involves running a scan of th ports. Try pOf, or nmap to run a port scan. This will show you the ports that are open on the machine, the OS, and can even tell you what type of firewall or router they are using so you can plan a course of action. You can activate OS detection in nmap by using the -O switch.
Find some path or open port in the system. Common ports such as FTP (21) and HTTP (80) are often well protected, and possibly only vulnerable to exploits yet to be discovered. Try other TCP and UDP ports that may have been forgotten, such as Telnet and various UDP ports left open for LAN gaming. An open port 22 is usually evidence of an SSH (secure shell) service running on the target, which can sometimes be bruteforced.
Crack the password or authentication process. There are several methods for cracking a password, including brute force. Using brute force on a password is an effort to try every possible password contained within a pre-defined dictionary of brute force software. Users are often discouraged from using weak passwords, so brute force may take a lot of time. You may try using Rainbow Tables for fastest password cracking. Notice that password cracking is good technique only if you already got the hash of password. Trying every possible password while logging to remote machine is not good idea, as it's easily detected by intrusion detection systems, pollute system logs and may take years to complete. Actually it's often much easier to find other way into system, than cracking password.
Get super user (root) privileges if targeting a *nix machine, or administrator privileges if taking Windows systems. Most information that will be of vital interest is protected and you need a certain level of authentication to get it. To see all the files on a computer you need super user privileges. This is a user account that is given the same privileges as the "root" user in Linux and BSD operating systems. For routers this is the "admin" account by default (unless it has been changed), for Windows, this is the Administrator account, etc. Just because you have gained access to a connection doesn't mean you can access everything. Only a super user, the administrator account, or the root account can do this.
Use various tricks. Often to gain super user status you have use tactics such as creating a "buffer overflow" which is basically causing the memory to dump and allowing you to inject a code or perform a task at a higher level then you're normally authorized. In unix-like systems this will happen if the bugged software has setuid bit set, so program will be executed as different user (superuser for example). Only writing or finding an insecure program that you can execute on their machine will allow you to do this.
Create a backdoor. Once you gained full control over machine, it's best to make sure you can come back one day. This can be done by backdooring important system service, such as SSH server. However your backdoor may be removed upon next system upgrade - really experienced hackers would backdoor the compiler itself, so every compiled software would've be potential way to come back.
Cover your tracks. Never ever let the administrator know that the system is compromised. Do not change the website (if any), do not create more files than you really need. Do not create any additional users. Act as fast as possible. If you patched server like SSHD, make sure it has your secret password hard-coded. If someone tries to login with this password, server should let him in, but shouldn't tell syslog about it.
TipsRead books discussing TCP/IP networking.
This article discusses what is known in the hacking world as "cracking". Hackers are those that built the internet, made Linux, and work on open source software. It is advisable to look into hacking, as it is respected and less likely to get you arrested.
Using these tactics on a popular corporate or government computer is asking for trouble unless you're a professional hacker. Keep in mind there are people a bit more knowledgeable than you who are protecting these systems for a living. Once found, they sometimes monitor intruders to let them incriminate themselves first before legal action is taken. This means you might think you have free access after hacking into a system, when in fact, you're being watched, and may be stopped at any moment.
Find information online related to hacking, or to even attend an "underground" hacking event, visit these sites:


enigmagroup.org A legal and safe network security resource where users test their hacking skills on various challenges and learn about hacking and network security. Also provided are articles, comprehensive and active forums, and guides and tutorials.
defcon.org Underground hacking event.
hackthissite.org Hacking site with a large selection of challenges to practice your skills in a safe and legal environment.
insecure.org Hacking tools and other software.
securityforest.com Tools, papers, exploits, and other reference material.
hellboundhackers.org Learn vital skills, complete training "missions, and talk with other experienced hackers to become better. Also get tools, and skills.



WarningsMisuse of this information may be a local and/or federal crime. This article is intended to be informational and should only be used for ethical purposes.
Do not delete entire logfiles, instead, just remove the incriminating entries from the file. What do you think would look more suspicious; logs with a few entries missing, or the entire log file destroyed?
Be extremely careful if you think you have found a very easy crack or a crude mistake in security management. A security professional that protects that system may be trying to track you be setting up a (honeypot).
Stay away from breaking into government networks. If you do find a vulnerability in such a network, the best plan of action is to inform the system administrator, and perhaps help them in patching the vulnerability.



Things You'll NeedA computer with a connection to the Internet.
A proxy is always a good idea.
An ip scanner
Petraflops help