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General Terms

Security Terms

Virus Terms

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Acronyms / Abbreviations

  Virus Terms...Click the Term to view the Definition.  

  What are Adware or Spyware programs?
Adware or Spyware programs are designed to snoop on your internet surfing behavior.

Originally designed to allow targeted advertising on selected web pages, they have become far more malicious. Adware or Spyware programs can force pop-up adverts or reconfigure your internet browser home page, often to gambling or pornographic web sites; track keystrokes, passwords, banking or credit card details and add additional toolbars to your browser. Even the less harmful ones can cause your computer to run slowly, cause your browser to hang or your computer to crash.
  What are the worst type of viruses?
The worst types of viruses are those containing a 'Remote Access' or 'Backdoor' component. Once infected, these types of viruses allow an attacker to gain control over or access into your computer.

Once in, an attacker can pretty much do whatever they want including copy files to your computer, run programs on your computer and even drop additional backdoors into your computer that may not be detected and removed by your virus software.

Following infection by a remote access or backdoor component virus, the only way to fully guarantee a system is 'clean' would be to completely wipe the system and re-install the entire operating system and all applications!
  What is a Botnet?
A network of zombie computers. A remote computer uses a collection of infected computers to carry out concerted malicious actions on the Internet, usually without the knowledge of the infected computers' owners.
  What is a Hoax Virus?
Electronic mail messages which warn of supposedly damaging viruses are now commonplace. These messages have become known as hoax viruses. The warnings they contain do not relate to any real viruses but burden electronic mail servers. If you receive a message warning of a virus, please DO NOT pass it on to your friends and colleagues.
  What is a Keylogger?
A special kind of trojan that records the keyboard and/or mouse activity on a PC and relays the information over the Internet to someone wishing to record passwords or other personal information.
  What is a Rootkit Virus?
A rootkit is a type of software designed to hide the fact that an operating system has been compromised, sometimes by replacing vital executables. Rootkits allow viruses and malware to 'hide in plain sight' by disguising as necessary files that your antivirus software will overlook. Rootkits themselves are not harmful; they are simply used to hide malware, bots and worms. Rootkits get their name from the Unix term for the primary administrator account called 'root' and 'kits,' which refer to the software pieces that implement the tool.

To install a rootkit, an attacker must first gain access to the root account by using an exploit or obtaining the password by cracking it or social engineering. Rootkits were originally used in the early 1990's and targeted UNIX operating systems. Today, rootkits are available for many other operating systems, including Windows. Because rootkits are activated before your operating system even boots up, they are very difficult to detect and therefore provide a powerful way for attackers to access and use the targeted computer without the owners notice.

Due to the way rootkits are used and installed, they are notoriously difficult to remove. Rootkits today usually are not used to gain elevated access, but instead are used to mask malware payloads more effectively.
  What is a Trojan?
Unlike a virus, a Trojan is not a self replicating program.

A Trojan hides its malicious actions by masquerading as something useful or desirable ? its name is derived from Greek mythology - Greek soldiers hide inside a wooden horse, which due to its desirability is brought into the city of Troy. Once inside, behind the defences, the Greek soldiers attack the previously impenetrable city.

A Trojan 'virus' uses the same principle; it relies on computer users sending the desirable (Trojan) program to friends and colleagues. You may think you have found and installed a fun new screensaver, cool free game or excellent new system utility, but you have in reality installed a harmful program onto your system designed to cause damage or disruption.
  What is a Virus?
A virus is a piece of malicious program code designed to disrupt or damage computer systems by adding itself (or a variant of itself) to commonly used system or program files. Viruses are self replicating, spreading from one 'infected' system to another. There are over 70,000 computer viruses in existence, with around 400-500 new viruses being discovered every month.
  What is a Worm?
A worm is a sophisticated piece of replicating code that requires no user interaction (such as opening an E-Mail or running a program) to spread.

Worms are designed to exploit vulnerabilities or security 'holes' in software applications or operating systems. With the advent of the internet, Worm viruses that exploit system 'holes' and require no user intervention can spread very quickly indeed!

The SQL Slammer worm, which exploited vulnerabilities in a Microsoft operating system, raced around the globe within 10 minutes of release, making it the fastest spreading computer virus ever!
  What is a Zombie Computer?
A Trojan horse is used to plant malware on an unsuspecting PC owner's system that allows a remote computer to use that system to send out spam or to perform other malicious tasks on the Internet without the owner's knowledge.
  What is Phishing?
Phishing is a technique whereby spammers or hackers imitate legitimate companies in an attempt to steal personal information such as bank details, credit card details, user names or passwords.

The scam usually takes the form of a carefully crafted E-Mail, designed to appear to come from a legitimate company, which contains a link to an external web page. The user is encouraged to click on the link, and enter personal information such as credit or bank details on the resulting web page.

Some Phishing scans are easily spotted due to bad grammar or poor spelling, but some can be very convincing indeed! Repeatedly targeted companies include Barclays Bank, Lloyds TSB, Citibank and Ebay (the online auction web site).
  What is Ransomware?
If you fall for the phony warning about your PC being infected and click on the link. it installs malware that demands payment and threatens to wipe out your files if you don't pay.
  What is Scareware?
Malware that pops up windows claiming your computer is infected and offers to clean it for a fee or tries to get you to click a link that will install a trojan. The malware can come from a drive-by-download or from a web page that has other malicious JavaScript on it.
  What is Spoofing?
Spoofing is a technique used by mass mailing viruses to 'hide their tracks' in an attempt to make detection more difficult.

To spread, mass mailing viruses send out hundreds or even thousands of infected E-Mail messages from a victim's computer. If the victims genuine E-Mail address is used, the infection can be easily traced and the virus quickly removed.

To get around this problem, mass mailing viruses use a technique known as spoofing. The virus searches the victims computer for alternative E-Mail addresses (i.e. potentially anyone the victim has ever corresponded with by E-Mail) and uses these alternative E-Mail addresses to form the 'FROM' fields on outgoing infected messages. Recipients of an infected E-Mail naturally look at the 'From' field to see where the infection came from, however if the virus uses spoofing, the 'From' field is false and the genuine source of the virus is undetectable.