Computer Security Glossary
A Glossary of Computer Security Related Terms
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A
ActiveX
ActiveX is a component object model (also reffered to as COM) developed by Microsoft. By using the COM architecture, added functionality is added to software applications by incorporating, seamlessly, pre-made components within the software package. Since Internet explorer allows ActiveX execution within web pages, this can be a possible channel for malicious software to infect or alter a local computer.
Administrator
Networks of computer systems are managed and overseen by an administrator, who is often involved in the design and day to day operations of that network. Security considerations depend highly on the administrator’s expertise.
Administrator rights
The ability to perform certain key operations on networked computer systems. These operations are restricted to administrators in order to prevent network security being compromised.
Adware
Adware refers to a type of software that exists in order to convey advertising to the operator. It often takes the form of ostensibly “helpful” programs such as toolbars, which actually end up changing the behaviour of browsers and other programs, causing them to display excessive advertisements.
Antivirus
A type of software that is built for monitoring systems for infection by viruses, scanning files to determine whether or not they contain virus payloads, and quarantining and removing infected files.
Auto-encryption
A feature of computer viruses that enables them to encrypt themselves upon infecting a system. This makes them significantly more difficult to detect and thusly remove.
B
Backdoor
Malicious software which provides a means through which hackers can access the user’s system through open ports, without alerting the user that anything is amiss.
Batch files
Batch files contain a number of instructions for running programs, altering the registry, and so on. Viruses often make use of batch files because they can carry out a number of system changes quickly, causing damage before administrators can react.
Boot virus
This refers to a virus that infects the boot sector of a computer, preventing the user from effectively booting into the operating system at all.
Botnet
A network of hacked computers that carry out instructions provided by bots; this type of array is often used to carry out systematic attacks such as DDoS attacks.
C
Cavity
A sophisticated technique by which viruses disguise their presence in infected files by injecting the virus code into “cavities”, or empty spaces in the original file’s code. This enables the infected file to maintain its original size, which makes detection significantly more difficult.
Cookie
Websites occasionally download a small file to a local computer to help it remember certain aspects of a browsing session - this is usually done to indicate that a user have previously visited, user settings (such as remembering who you are between visits) or targeting for marketing. Generally, only the website that creates the cookie can utilize it's own cookie, so as not to cross identifier information across different websites. However, used nefariously, cookies can be used to show personally identifiable information that a browser session has passed between the client and server.
Crimeware
Malicious software or viruses intended to collect personal information for the purpose of enabling criminal behaviour, such as the collection of credit card numbers with intent to commit fraud.
Cybercrime
Any crime that is committed by using a computer, hardware device, or network. The device or computer may the the facilitator of the crime, the target of the crime, or the agent of the crime.
D
Damage Level
This is a numerical assessment of the degree of damage that a virus can cause to a computer system. Something like adware might have a relatively low damage level, while a boot virus might have a relatively high damage level.
Database
A table of indexed data used in modern web applications, wherein user information is collated and stored in an indexed manner for easy retrieval and organization. This is critical for the function of web applications, but also makes an appealing target for viruses, before personal information is readily accessible.
DDoS
This “Distributed Denial of Service” attack refers to a coordinated attack wherein multiple computers send endless requests for a service, with the intention of overloading that server and preventing it from effectively operating. While the server is overloaded, hackers can often break in through compromised ports and cause damage to a system.
Dialer
A type of virus that is used to redirect internet connections. This can be done for a variety of purposes, from simple malice such as causing the user extra expenses, to more malicious designs such as enabling hackers to perform illegal activities from the guise of the user’s computer and IP address.
E
Emerging threats
Computer security threats that can be unknowingly downloaded from the internet, instant messaging, or email messages. Some examples of these are:
- Remote access programs, allows access over the internet to a local machine to gather information of alter a local computer
- Dialers, scripts that take control of your modem and dial a toll number to rack up revenue for the script publisher.
- Joke Programs, programs that interrupt or change the normal behavior of your computer, ie; switching the functionality of your mouse buttons.
- Hack Tools, used by hackers to gain access to a computer, such as a keystroke logger or password catcher.
Encryption
Encryption refers to the encoding of viruses in a way that prevents them from being detected or extracted. Removing an encrypted virus is significantly more difficult than an unencrypted virus.
F
File Allocation Table (FAT)
A segment of a hard drive that defines the memory address where each file on the disk is stored. It is a popular target for malicious viruses, as a corrupted file allocation table can prevent users from accessing their data.
File Transfer Protocol (FTP)
An internet protocol designed for the transmitting of large files across TCP/IP. Ports designated for FTP may be left unprotected and can be attractive targets for hackers.
Firewall
Either a piece of software or a hardware device that performs the function of blocking internet traffic across certain ports, or preventing certain programs from connecting to the internet. A key utility for protection against viruses.
Freeware
Software that is readily available for download and be used for free. This can be a potential backdoor opener for cybercriminals. Never install free software from a source that cannot be trusted.
H
Hacker
A general term used to describe an individual who attempts to gain unauthorized access to computer systems.
Hyper Text Transfer Protocol (HTTP)
A protocol designed to allow webpages to be transmitted across TCP/IP. Generally harmless, but some ingenuous hackers can take advantage of the protocol to infect systems that lack sufficient antivirus protection.
I
Identity Theft
The practice of stealing critical personal information such as names, addresses, social security numbers, and financial data, that enables a hacker to carry out fraudulent activities. For instance, purchases may be made with a stolen identity, for which the victim may be financially liable.
J
JavaScript
A programming language that was developed for the purpose of allowing dynamic content in web sites. While this type of scripting is critical for many modern web features, it also has the potential to introduce security vulnerabilities through which systems might become infected.
K
Keylogger
A program that runs on a user’s system undetected, and which collects information every type the user strikes a key. This information is then relied back to the hacker who infected the system with the keylogger. This is used to steal important personal information such as system password or financial information.
L
Logic Bomb
This is a type of virus which uses a computer’s inherent logic to undermine and harm the system. For example, it might feed a system contradictory instructions over and over as a way of taxing the system’s resources in an endless and fruitless attack. This leaves the system vulnerable to other forms of attack.
M
Macro
A simple script or software program that helps automate routine and repetitive tasks. Commonly used and/or executed in Microsoft's Work and Excel programs.
Macro Virus
This is a type of virus that embeds itself in programs that offer macro functions, such as the Microsoft Office suite. Whenever a user runs an infected macro in a program such as MS Word, the virus is triggered and infects the system.
Malware
A portmanteau for “malicious software,” this term refers to any program that is written to cause some sort of destruction in a system, or provide vulnerabilities for hackers to gain unauthorized access.
Master Boot Record (MBR)
A segment of a computer’s hard drive that contains information about the location of the computer’s operating system. This is essential in order to allow a system to boot at all. Consequently, many viruses target the master boot record as a way to totally down a system.
Mobile Code
A Web-based application (often scripted as a form of ActiveX controls, Visual Basic scripts, or a Java™ applet) that is used to enhance the usability, interactivity, or appeal of a Web page. They can be used to deliver malicious payloads due to the fact that the execute automatically when web pages are downloaded.
N
Network
A term used to refer to a collection of computers which are linked together by means that enable them to communicate with one another, share files, and so on. The internet is one giant network, but the term can also refer to smaller linked networks, such as the linked computers in an office building or school. Networks are prime targets for virus attacks, as the infection can rapidly spread from one machine to the next.
O
Online Fraud
Any type of fraud that uses email, Web sites, chat rooms, or message boards. These vehicles are used to present fraudulent solicitations to potential victims, conduct fraudulent transactions, or transmit stolen money to financial institutions or others connected with the crime.
Online Transaction Security
A set of security features available to web surfers when banking online, shopping, submitting account numbers, passwords, or any confidential information. These measures are mostly used when consumers are most vulnerable to hackers and criminals.
Operating System
A key type of software that enables users to interact with a computer in a user-friendly manner. Instead of having to transmit instructions to the computer in machine-code, an operating system allows users to select commands in an intuitive fashion. Often the target of virus attacks, because the loss of an operating is profoundly devastating to a system.
P
Password Stealer
A type of virus that functions by searching for and stealing user’s passwords, and then transmitting them back to the hacker in question. This enables the hacker to access websites as the user, which could include highly sensitive information, such as online banking.
Payload
This term refers to the effects of a virus. An adware’s “payload” is the display of advertisements, while a trojan’s payload might be the malicious code hidden inside the innocuous outer software.
Pharming
An attempt to defraud web surfers by hijacking a Web site's URL or domain name and redirecting them to an similar looking site, where requests for personal or confidential information are made.
Phishing
A non-directed type of hack that involves sending mass messages to large groups of people in the hopes that at least a few of them will respond and expose themselves to attack. For example, an email chain letter that pretends to be from a reputable company and asks people to log on and change their passwords; in fact, the email would lead the user back to the hacker’s website where, if they typed in their old passwords, the information could be stolen. A very crude but effective method of gathering information.
R
Rootkit
This is a type of software that is used to hide or obscure the presence of a virus on a system. It does so by preventing the user from seeing processes associated with the virus, altered registry entries, and so on.
S
Shareware
Software that requires registration, licensing, paid or service activation after a time limit but is free to download and distribute. It can pose a potential danger if downloaded from an untrusted source.
Spam
The digital equivalent of “junk mail.” Spam refers to unwanted email, which often contains advertisements. Spam is frequently used by hackers in order to obtain information from uneducated users. For instance, a widely targeted phishing campaign might involve the use of spam.
Spyware
A program that secretly relays confidential information from one computer to another. Usually downloaded unknowingly from the Web, they are typically deployed via shareware or freeware applications, in emails, and instant messenger programs. Often unknowingly downloaded by accepting an End User License Agreement from certain software.
Stealth
- A certain type of computer virus or malware that operates without alerting common means of detection.
- A network port or computer that are invisible to hacking attempts or programs.
T
Threat Level
A numerical representation of the overall threat posed by a virus. Viruses with higher threat levels are able to cause more substantial lasting damage to a system and its operators, while a virus with a lower threat level may only cause temporary, minor, or reversible damage.
Trojan
Programs that pose as innocuous or helpful programs (often anti-virus programs or programs that purport to increase computer performance), but which actually contain malicious code that is carried out once the software is installed on a user’s system.
Tunneling
A method by which viruses obscure themselves from detection by antivirus software. In this sense, a form of encryption.
V
Virus
Any type of software that is intended to produce undesirable or harmful behaviour within a computer system.
Virus Definition
A file which specifies pertinent details about a virus such as its file size, common associated file names, and so on. The definition file assists antivirus software in locating infections.
Vulnerability
This term refers to any means by which a system might be infected by a virus. It could refer to an open port on a machine, a compromised password, or even a user who freely leaks private information.
W
Wild Virus
A virus or viruses that are not yet indexed in research labs and have infected one or more users not associated in the anti-virus community. Infection occurs as a result of nominal day-to-day activity and are not at the top of Norton's priority list.
Windows Registry
A large file which contains vital information about an operating system’s processes and configuration. Often targeted by viruses because if the registry is corrupted, the system’s functionality is severely compromised.
Worm
Worm is a type of virus that makes copies of itself as a means of preventing its easy extraction from a system. It can also be a program or script that can replicate without infecting other systems or programs. Sometimes the replication channel is by jumping disk to disk, but with the progression of the Internet, worms these days utilize networks and email systems in order to spread onto other computers.
X
XOR - OR-Exclusive
One of the most common methods by which viruses enact encryption upon themselves.
Z
Zombie
In this context, a zombie is a computer that has been hacked, and which can now receive and carry out instructions from remote bots. When a hacker gains remote control of a system and begins sending instructions to it, that system is said to be a zombie.