What is an Email Virus?

An e-mail virus is computer code sent to you as an e-mail note attachment which, if activated, will cause some unexpected and usually harmful effect, such asdestroying certain files on your hard disk and causing the attachment to be remailed to everyone in your address book. Although not the only kind of computer virus, e-mail viruses are the best known and undoubtedly cause the greatest loss of time and money overall. The best two defenses against e-mail viruses for the individual user are: (1) a policy of never opening (for example, double-clicking on) an e-mail attachment unless you know who sent it and what the attachment contains, and (2) installing and using anti-virus software to scan any attachment before you open it. Business firewall servers also attempt, but not always successfully, to filter out e-mail that may carry a virus attachment. The Melissa virus, macro virus and the ILOVEYOU virus are among the most famous e-mail viruses. Each of these also spawned copycat variations with different words in the subject line.

Computer Cookies

What is a Computer Cookie?
A computer cookie is a tiny text file that is saved to your hard drive by a website programme. This file contains information about your searches and behaviour on the website. It is saved without your consent or knowledge meaning you really have no computer privacy. Whenever you next visit the site, it identifies you by looking-up your cookie. This is how many sites are able to 'greet' you when you return, to remember your password, or to recommend products just for you.

Computer cookies are programmed to collect certain information about you. For Google, your cookie file could contain search terms, a unique identification number, and your IP address. It's designed to monitor your movements and report back to the host website.

What Are Computer Cookies Used For?
As they gather and record your information, computer cookies are creating a valuable record of your behaviour and your statistics. Online companies use them to carry out behavioural targeting.

Behavioural targeting is a method which enables companies to identify trends and predict your actions. When you, like thousands of others, were searching for driving directions using Google, the search engine giant identified a common need and quickly established 'Google Maps'. If enough of us were to boycott 'Google Maps', clicking on another direction provider, Google would probably recognise this trend and relegate Google Maps to a minor page.

What Should I Do About Computer Cookies?
When cookies were first introduced, nobody knew they were there, and nobody was able to stop them - no one realised they threatened computer privacy. But this soon changed when people in-the-know started to kick up a fuss, and eventually cookie controls were added to most browser programmes. Because cookies gather so much personal information, and particularly because you don't always know what that includes, we recommend taking action to protect yourself against cookies for your computer privacy. There are a few ways to fool the system - the first action is essential for anyone using the web

What is a Computer Worm?

A computer worm differs from a computer virus in that a computer worm can run itself. A virus needs ahost program to run, and the virus code runs as part of the host program. A computer worm can spread without a host program, although some modern computer worms also use files to hide inside. The original computer worm was (perhaps accidentally) unleashed on the Internet by Robert Tappan Morris in1988. The Internet Worm used sendmail, fingerd, and rsh/rexec to spread itself across the Internet. The SQL Slammer Worm of 2003 used a vulnerability in Microsoft SQL Server 2000 to spread itself across the Internet. The Blaster Worm, also of 2003, used a vulnerability in Microsoft DCOM RPC to spread itself. The Melissa worm of 1999, the Sobig worms of 2003 and the Mydoom worm of2004 all spread through e-mail. These worms shared some features of a trojan horse,in that they spread by enticing a user to open an infected e-mail attachment.

Common Computer Viruses

Below is a list of the most common types of viruses, Polymorphic Viruses A polymorphic virus is an encrypted virus that hides itself from anti-virus through encrypted (scrambled) data and then decrypts itself to beable to spread through the computer. The thing that makes it hard for anti-virus software to detect polymorphic viruses is that the virus generates an entirely new decryption routine each time it infects a new executable file, making the virus signature different in each signature. Stealth Viruses A Stealth virus hides the modifications made to files and boot records by modifying and forging the results of calls to functions, therefore programs believe they are reading the original file and not the modified file. A good anti-virus software will probably detect a stealth virus due to the fact that a stealth virus attempts to hide itself in memory when a anti-virus software is launched. Slow Viruses A Slow virus is a difficult virus to detect due to the fact it only modifies and infects files when they have been modified or copied. Therefore the original file will not be infected by the actual copied file. A good way to protect yourself against slow viruses is by using an integrity checker or shell. Retro Viruses A Retro virus attacks the anti-virus software designed to delete it. The retro virus usually attempts to attack the anti-virus data files such as the virus signature store which disables the ability of the anti-virus software to detect and delete viruses. Otherwise the retro virus attempts to alter the operation of the anti-virus software. Multipartite Viruses A Multipartite virus attempts to attack and infect both the boot sector and execuatble files at the same time. Armored Viruses A Armored virus attempts to protect itself from anti-virus soaftware by trying to make anti-virus software believe it is located somewhere else. Therefore the Armored virus has made itself more difficult to trace, disassemble and understand. Companion Viruses A Companion virus creates a companion file for each execuable file the virus infects. Therefore a companion virus may save itself as scandisk.com and everytime a user executes scandisk.exe, the computer will load scandisk.com and therefore infect the system. Phage Viruses A Phage virus is a very destructive virus that re-writes a executable program with it's own code, rather than just attaching itself to a file. Therefore a Phage virus will usually attempt to delete or destroy every program it infects. Revisiting Viruses A Revisiting virus is a worm virus and attempts to copy itself within the computers memory and then copy itself to another linked computer using TCP/IP protocols. The Morris Worm virus in the late 1980's was the first major virus threat to hit the Internet.

Spybot

Along with spyware and adware detection anddisinfection capabilities, Spybot-S&D can repair the Registry, Winsock LSPs, ActiveX objects, browser hijackers and BHOs, PUPS, computer cookies, trackerware, heavy duty, homepage hijackers, keyloggers, LSP, tracks,trojans, spybots, revision, and other kinds of malware. It can also to some extent protect a user's privacy by deleting usage tracks like tracking cookies. Spybot-S&D also includes an"Immunize" feature to block the installationof spyware before it occurs e.g. by modifying the hosts file. Another tool included in Spybot-S&D is a file shredder, for the secure deletionof files. Spybot-S&D is not intended to replace anti-virus programs, but it does detect somecommon trojans.

Spybot-S&D also recently added an anti-rootkit function.

The TeaTimer module can be optionally enabled, providing a level of active, real-time protection from undesirable registry changes and the like. This comes in the form of pop-ups which alert the user to registry changes, and ask for approval before allowing the change. Registry changes only tend to be made when programs are installed/uninstalled/updated, so random changes can indicate the presence of malicious software.

Some programs ship with attached spyware or adware and refuse to run when the undesired co-programs are removed; newer versions of Spybot replace the spyware binaries with inert dummies (designed to fool programs which require the spyware's presence).

In order to efficiently detect recently created programs, detection updates are released weekly along with other improvements such as added languages and better heuristicsalgorithms. These updates are downloaded from within the software from a variety of mirrors and are then automatically installed.

Spybot-S&D is available for all versions of Windows from Windows 95 and up, and offers more than two dozen different languages and several skins to users. Instructions are available on the website to enable users to design their own skins.

What is a Trojan Horse Virus?

A Trojan Horse Virus is a common yet difficult to remove computer threat. This is a type of virus that attempts to make the user think that it is a beneficial application.

A Trojan Horse virus works byhiding within a set of seemingly useful softwareprograms. Once executed orinstalled in the system, this type of virus will startinfecting other files in the computer.

A Trojan Horse Virus is also usually capable of stealing important information from the user's computer. It will then send this information to Internet servers designated by the developer of the virus. The developer will then be able to gain a level of control over the computer through thisTrojan virus. While these things take place, the user will notice that the infected computer has become very slow or unexpected windows pop up without any activity from the user. Later on, this will result to a computer crash.

A Trojan Horse virus can spread in a number of ways. The most common means of infection is through email attachments. The developer of the virus usually uses various spamming techniques in order to distribute the virus to unsuspecting users.

These emails contain attachments. Once the user opens the attachment, the Trojan Horse Virus immediately infects the system and performs the tasks mentioned above.

Spam

Spam is a type of unsolicited electronic 'junk mail' that is often sent out to many people at the same time. Theseunwanted messages may be sent by email, but may also be sent as text messages tomobile devices, includingsmartphones. Spam messages mayadvertise or offer youunsolicited goods, services, land, or business and investment opportunities."Scam" spam messages may be used to try to trick ordisadvantage you, for example, by offering you get-rich-quick schemes. Remember, if it sounds too good to be true, it probably is! However, not all messages are'spam.' Businesses are allowed to send you 'commercial electronic messages'provided they meet three tests set out in the Spam Act. These tests are that the message must: Be sent with your consent Identify the sender Include a functional unsubscribe mechanism (in other words, you can ask not to receive any more messages). Messages that don't meet these tests are generally 'spam' and are unlawful under theSpam Act.