What is disk defragmentation? - Security Term

Disk defragmentation describes the process of consolidating fragmented files on your computer's hard disk.

What is fragmentation? - Security Term

(1) Refers to the condition of a disk in which files are divided into pieces scattered around the disk. Fragmentation occurs naturally when you use a disk frequently, creating, deleting, and modifying files. At some point, the operating system needs to store parts of a file in noncontiguous clusters. This is entirely invisible to users, but it can slow down the speed at which data is accessed because the disk drive must search through different parts of the disk to put together a single file.

What is Proxy Server? - Security Term

In an enterprise that uses the Internet, a proxy server is a server that acts as an intermediary between a workstation user and the Internet so that the enterprise can ensure security, administrative control, and caching service. A proxy server is associated with or part of a gateway server that separates the enterprise network from the outside network and a firewall server that protects the enterprise network from outside intrusion.

What is Server? - Security Term

1) In information technology, a server is a computer program that provides services to other computer programs (and their users) in the same or other computers.

2) The computer that a server program runs in is also frequently referred to as a server (though it may be used for other purposes as well).

3) In the client/server programming model, a server is a program that awaits and fulfills requests from client programs in the same or other computers. A given application in a computer may function as a client with requests for services from other programs and also as a server of requests from other programs.

What is Storm? - Security Term

The Storm Botnet is a distributed computer network consisting of computers remotely controlled without their owner's knowledge. Computers in the Storm Botnet are home and small office machines running the Microsoft Windows operating system which have been infected by the Storm worm. Storm got it's name as the worm was first spread though spam email with the subject "230 dead as storm batters Europe." Today, the Storm Botnet is considered to be the largest botnet in the world, with as many as 5 million computers under it's control. Efforts to combat Storm have been met with targeted resistance, suggesting that artificial intelligence and automated adaptive defense techniques are being utilized.

What is data breach? - Security Term

A data breach is an incident in which sensitive, protected or confidential data has potentially been viewed, stolen or used by an individual unauthorized to do so. Data breaches may involve personal health information (PHI), personally identifiable information (PII), trade secrets or intellectual property.
The most common concept of a data breach is an attacker hacking into a corporate network to steal sensitive data. However, not all data breaches are so dramatic. If an unauthorized hospital employee views a patient's health information on a computer screen over the shoulder of an authorized employee, that also constitutes a data breach.

What is browser hijacker (hijackware)? - Security Term

A browser hijacker (sometimes called hijackware) is a type of malware program that alters your computer's browser settings so that you are redirected to Web sites that you had no intention of visiting. Most browser hijackers alter default home pages and search pages to those of their customers, who pay for that service because of the traffic it generates.

What is svchost.exe? - Security Term

What is the svchost.exe file? Why do I have multiple svchost.exe processes running in Task Manager? Is svchost.exe a virus or trojan? These are the most frequently asked questions about this process.

What is SQL Injection? - Security Term

SQL injection is a type of computer security exploit in which an attacker can gain access to remote database systems. Using a carefully-constructed value for a form field, such as a name or email address, an attacker can fool the application into requesting data from a database which he would otherwise not have access to. SQL injection attacks are similar to XSS attacks in that the attacker is exploiting an application's regular input vectors. Also in common with XSS attacks, SQL injection attacks can be prevented by simple input filtering and validation before the data is passed on for storage or processing.

What is spam? - Security Term

Spam refers to both the process of sending unsolicited messages via the Internet, and to the messages themselves. However, the term "unsolicited messages" is open to debate, and as such what is considered spam varies widely. In the strictest sense, spam is any email advertisement, other than those specifically requested by the receiver. However, even this strict definition is debatable, as very often EULA's and service agreements contain clauses for the sending of advertisements. And few users read all twelve pages of every EULA that they accept.

What is a Rootkit? - Security Term

A rootkit is a type of computer program that hides its presence from the administrator of the machine. Usually installed as malware, rootkits are very difficult to detect and remove because they erase all evidence of their presence. Often, the only visible symptoms of a rootkit may be an unexplainably busy CPU or unusual network traffic. With today's high-speed CPU's and high bandwidth network connections, rootkits are almost impossible to identify. Typically, rootkits are used to cloak keyloggers and other spyware, distribute spam, or to provide privileged access to an unauthorised entity. The term is named for the Unix privileged user account, root, although today rootkits are available for most major operating systems including Linux, Mac OS-X, and Microsoft Windows.

What is Gator? - Security Term

Gator was a computer program by Claria Corporation. Notorious as one of the first widespread spyware applications, Gator had inadvertently created a revolution in consumer backlash against irresponsible computer program design and malware proliferation. While various computer security vulnerabilities, such as viruses, had been familiar to security experts for years, Gator was the first program to cause widespread concern among nontechnical home computer users. Although most installations of Gator were performed with full disclosure regarding the nature of the program, many users who did not read it's EULA were unaware of the program's activity. While this fact had saved Claria Corporation from several lawsuits, unfortunately it had not stimulated an increase in consumer awareness regarding the need to read EULAs and to understand them. Additionally, Gator could not be removed via standard software removal procedures.

What is DomainKeys Identified Mail? - Security Term

DomainKeys Identified Mail is a an email authentication method designed to control spam and phishing. Developed by Yahoo, DKIM is now endorsed by major Internet and email related organizations such as the PGP Corporation, Cisco Systems, and the developers of Sendmail. While other competing email authentication methods have been proposed, such as SenderID and Sender Policy Framework, only DomainKeys Identified Mail is being evaluated as a possible Internet Engineering Task Force standard. Currently, several large email service providers such as Yahoo, Gmail, and AOL utilize DKIM technology in emails sent from their systems.

What is a bug? - Security Term

A bug is an error in a computer program or hardware. While usually the result of programmer error or oversight, bugs can also be introduced into a program through compiler error, incorrect assumptions about hardware or software interfaces, or can be intentionally coded into software to create obfuscated interfaces or back doors. While bugs often cause software to crash or produce unexpected results, certain types of software bugs can be exploited to gain unauthorized access to otherwise secure computer systems.

What is a Buffer Overflow? - Security Term

A buffer overflow is a type of computer security exploit which allows a program to perform functions that it is not designed to do. The responsibility for preventing the possibility of exploit lies in the programmer, however this requires proper planning and knowledge. While most programming courses teach proper coding techniques that prevent the possibility of a buffer overflow, coders who learn on their own tend to produce exploitable code. Thus, modern compilers have been designed to detect possible exploits and warn about them. Despite this, the compiler cannot be 100% efficient at catching exploits and proper coding guidelines must always be followed.

What is ActiveX? - Security Term

ActiveX is a series of computer program distribution and runtime technologies. Developed by Microsoft, ActiveX technologies have been incorporated into almost all of Microsoft's products released in recent years including Windows, Word, Excel, and Internet Explorer. ActiveX-enabled programs can embed features found in other enabled programs, and can incorporate new features within an ActiveX component. For instance, Internet Explorer can open an Excel spreadsheet via ActiveX object linking, and incorporate all the features of Excel within itself. Similarly web designers who wish to incorporate a features not implemented within any of Microsoft's products can write the features as an ActiveX component in any programming language that support it.

What is sandbox? - Security Term

Using the Java programming language and development environment, the sandbox is the program area and set of rules that programmers need to use when creating Java code (called an applet) that is sent as part of a page. Since a Java applet is sent automatically as part of the page and can be executed as soon as it arrives, the applet can easily do harm, either accidentally or as the result of malicious intent, if it is allowed unlimited access to memory and operating system services. The sandbox restrictions provide strict limitations on what system resources the applet can request or access. Essentially, the programmer must write code that "plays" only within the sandbox, much as children are allowed to make anything they want to within the confined limits of a real sandbox. The sandbox can be conceived as a small area within your computer where an applet's code can play freely - but it's not allowed to play anywhere else.

What is patch (fix) ? - Security Term

A patch (sometimes called a "fix") is a quick-repair job for a piece of programming. During a software product's beta test distribution or try-out period and later after the product is formally released, problems (called bug) will almost invariably be found. A patch is the immediate solution that is provided to users; it can sometimes be downloaded from the software maker's Web site. The patch is not necessarily the best solution for the problem and the product developers often find a better solution to provide when they package the product for its next release.

What is zero-day exploit ? - Security Term

A zero-day exploit is one that takes advantage of a security vulnerability on the same day that the vulnerability becomes generally known. There are zero days between the time the vulnerability is discovered and the first attack.

What is white hat ? - Security Term

White hat describes a hacker (or, if you prefer, cracker) who identifies a security weakness in a computer system or network but, instead of taking malicious advantage of it, exposes the weakness in a way that will allow the system's owners to fix the breach before it can be taken advantage by others (such as black hat hackers.) Methods of telling the owners about it range from a simple phone call through sending an e-mail note to a Webmaster or administrator all the way to leaving an electronic "calling card" in the system that makes it obvious that security has been breached.