Hacking Terms

Back Door

Programmers and system managers will often code special hidden ways to get into a system into their programs. Oftentimes these are done simply to make it easier to log in; for example, a systems operator might find it tiring to enter two passwords every time he needs to log in so he might create a simpler way. Sometimes they are done to allow people to log in after leaving a job (consultants may do this so they can gain access later), and a hacker might crack into your system and then create a special way in so he can come back later. The main point here is a back door always short-circuits the front line security.

Cracking

Cracking is illegally breaking into systems for whatever reasons, or using a computer illegally. In general, much of what the public refers to as "hacking" should really be called "cracking".

Data Diddling

Modifying data. For example, changing credit card numbers or modifying social security information.

Denial Of Service Attack

Attacks which attempt to overwhelm a computer system. These often take advantage of bugs or send data so quickly that a computer can do nothing else but serve the request. One typical denial of service attack is to send malformed packets as fast as possible. The receiving computer finds it can do nothing else but handles these packets. (See "Hacker Notes - Denial Of Service Attacks" for more information).

Distributed Denial Of Service Attack

In order to make it more difficult to track down the source of a denial of service attack, it can be launched from two or more different machines. Attacks of this sort are often spread via email trojan horses, and quite often the attacking machine's owner is totally unaware of what's going on.

Dumpster Diving

Many system managers (at least those who don't know any better) throw away computer printouts and other information into their normal trash. The term Dumpster Diving comes from the habit of literally getting into trash containers, looking for these listings. This is essentially a way to get information about the computer systems of the company who threw out the trash.

Easter Egg

A special kind of trojan horse, generally added to a program by the developers. These are undocumented functions which are usually intended to be funny in some way.

Email Bomb 

An attempt to send so many email messages to an email server or inbox that it becomes overwhelmed. See "Hacker Notes - Email Bombs" for more information.

Hacking

Much of what the media covers is actually cracking, not hacking. In the "old days" hacking referred to learning about computers by hands on study and analysis. Today hacking generally means any illegal use of a computer system.

Hacktivism

Hacking which is motivated by political or ideological reasons. For example, defacing a web site in order to promote political freedom for someone.

Impersonation

Simply put, pretending to be something that someone is not. In social engineering, this might be as obvious as pretending to be the phone repairman in order to tap into the phone lines.

Latency

The amount of time that must pass before a time bomb or logic bomb triggers the payload.

Logic Bomb

This is a piece of code inserted by a hacker (or a trojan horse) which is triggered by an event. It may be as simple as a date passing or as complicated as the termination of an employee. The point is the damage does not occur until a specific thing (or things) has occurred.

Malware

Malicious software, including viruses, email bombs, trojan horses, worms, logic bombs, time bombs, back doors and so on.

Master Program

A program run by a hacker or hackers which allows zombies to be controlled. The master program is used to transmit instructions to the zombies, usually to direct distributed denial of service attacks.

Payload

The part of a virus, trojan horse or other malicious code which actually performs the intended task.

Root Kit

A set of tools available to hackers to allow them to gain access to root (privileged) functions on a server.

Social Engineering

Using various social skills (such as lying or conning) to attempt to get someone to hand over a password, access code or simply access to a computer. 

Spam

Spam is the sending of unsolicited, undesired email messages in mass, usually for advertising purposes (although occasionally for political or religious ends). Often the email addresses are obtained involuntarily and without the knowledge of the owners by scanning web pages (this is known as email harvesting), purchasing email lists or just plain making them up.

Spoofing

Quite simply, lying. This often refers to the changing of the TCP/IP address in a packet in order to hide the originating computer, or the modification of the return address in an email in order to mask the sender.

Time Bomb

This is simply some code on a computer which is does not immediately trigger. Instead, it is set to cause it's damage at some point in the future.

Trojan Horse

Similarly to the legend, a Trojan Horse is a malicious piece of code which appears to be something useful or desirable.

Virus

A destructive piece of code which infects or inserts itself into normal code on a computer. Many viruses install themselves into the boot sector of a disk so as to reload each time a computer boots, or add themselves to privileged programs on the computer. Many of the things which most people refer to as viruses are actually worms.

Worm

A worm is similar to a virus in that it sends itself from system to system. However, a worm does not integrate itself into code on the target system. Instead, it just executes and does it's damage. Virtually all of the things that the public thinks of as viruses are actually worms.

Zombie

A Zombie is a program or piece of code which is injected into a system. These zombies then wait for commands from hackers, and perform their bidding. Generally, zombies are used in distributed denial of service attacks, and are often spread as worms through newsgroups, IRC chats and email messages. It is quite common for systems to be infected with zombies without their users knowledge, and since no damage results to their system they may never know they are infected.