| In addition to the common methods of | | | | specific time, launching a combined attack |
| spreading through email attachments, boot | | | | from all the infected machines against the |
| infections and program infectors, there are | | | | primary target. |
| other ways by which viruses spread to your | | | | |
| computer. These include: | | | | As you can see, your computer can be hijacked |
| | | | without your knowledge and then used in a |
| Infection by Disk(Floppy, Zip, CD's, Tapes, | | | | major attack against an unsuspecting company. |
| etc.) | | | | However with up-to-date virus/firewall |
| | | | protection, your computer will be immune to |
| Floppy disks, though not as commonly used as | | | | such hijacking. |
| in the past, are still a very common way | | | | |
| viruses being spread from machine to machine. | | | | Other ways by which virus spreads |
| Anyone with an infected machine, using a | | | | |
| floppy disk to copy and save files, can also | | | | Other sources of viruses have been found to |
| copy and transfer the virus. Any use of that | | | | be the result of software downloads available |
| same removable disk, by any user, at any time | | | | over the Internet. Software patches, drivers, |
| in the future, will most likely contaminate, | | | | demonstration software, from reputable |
| or re-contaminate the any computer it is used | | | | companies, generally carries little risk. |
| with. The only way to properly clean an | | | | However, the Internet is also filled with |
| infected floppy disk is to perform a | | | | "unofficial" software, pirated programs, and |
| low-level format. The normal Windows(tm) | | | | low-budget software from questionable sources |
| "format disk" is often not enough. | | | | that may be intentionally or unintentionally |
| | | | infected with viruses. Files downloaded |
| With CD's, all the above holds true with the | | | | directly from the Internet (either through |
| exception that an infected CD can never be | | | | file-sharing programs or direct download from |
| cleaned. To get rid of an infected CD, you | | | | websites), are among the fastest growing |
| need to put it in the trash and never use it | | | | sources of computer virus infections. |
| again. | | | | |
| | | | Email, with its nearly universal availability |
| Infection from Networks | | | | and ease of use; chat rooms and messenger |
| | | | systems, not only make communication simple |
| Peer-to-Peer network, Local Area Networks | | | | and quick, also make the transmission and |
| (LAN), a Wide Area Network (WAN), Wireless | | | | re-transmission of infection simple and |
| Networks, and the Internet, are all computer | | | | alarmingly fast. Creators of newer viruses, |
| networks. They all have the same basic | | | | and internet worms specifically target these |
| purpose; to share software, and information | | | | systems because they are widely used, and are |
| resources between two or more computers. As | | | | often built right into the operating system |
| with anything else that is shared between | | | | and used with default settings making them |
| computers, networks let users share files, | | | | much easier to attack and exploit. |
| and wherever files are shared, viruses can be | | | | |
| shared and spread. | | | | As a point of reference, Internet Explorer, |
| | | | and Outlook/Outlook express email clients are |
| Most network virus/worm/Trojan activity is | | | | two of the applications most targeted by |
| like what we described earlier, although more | | | | Internet viruses and worms. Why? Because they |
| and more examples of automatic mass mailing | | | | are installed on more computers around the |
| attacks, system resource attacks are being | | | | world than any other software, and they are |
| found. | | | | installed 99% of the time with default |
| | | | settings (which means virus programmers have |
| Recently many attacks are designed to | | | | an easy blueprint to follow). |
| specifically target major corporate interests | | | | |
| (Microsoft, eBay, Amazon, major Banks etc.) | | | | If you use an email system or instant message |
| in an attempt to disrupt their online | | | | system that is installed automatically with |
| services. Very generally these are called DOS | | | | your computer's operating system you need to |
| (denial of service) attacks. The way they | | | | install and use current antivirus software. |
| most commonly work is by secretly infecting | | | | You also need to learn how to turn off |
| thousands of local user computers (like the | | | | certain default settings that can leave your |
| one you are using right now), and then at a | | | | system open to very easy attack. |