F Secure Anti Virus Article

Antivirus Protection: How To Combat Computer Viruses

To keep a computer free from viruses all one has to do is buy software from reliable vendors only and refrain from opening unanticipated email attachments. Email attachments are possible virus carriers and one popular method of virus distribution is through accessing the address book of an infected computer and despatching emails with attachments to all the addresses in the book. An email attachment from an apparently known sender can actually contain virus as it is easy to fake sender’s addresses.

The Melissa virus which crippled computers worldwide in 1999 used the above technique. Initially it was posted to a news group through a Word document. When it was downloaded by a host computer and opened it multiplied itself by sending the same document to the first fifty addresses in the address book. Thus it spread to hundreds of computers worldwide in a matter of few hours slowing down the entire Internet network.

The ILOVEYOU virus of 2000 operated much in same fashion. When the mail was double clicked, it sent its own copies to all the addresses in the address book of the infected computer. The threat of computer viruses is still there very much with us with new viruses cropping up through out the world everyday.

Action to be taken to tackle computer virus

Antivirus Software

A number of antivirus software packages is available commercially for less than $50 as well as in freeware version. They work by examining email attachments and files on arrival and later scanning them at preset intervals. They look for virus ‘signatures’ in the files in order to detect them.

On detecting a virus, the antivirus software alerts the user and gives option of repairing the files of virus or quarantine the virus by which the virus is made inactive or deleting the infected files.

Updates

The signatures of viruses are nothing but computer instructions in a particular pattern similar to biological virus. These patterns are evolving with each new virus and hence the antivirus software needs to be updated regularly in order to be able to identify the new virus. The characteristics of the new virus signatures are stored in the updated files. Most of the antivirus software refreshes these files online automatically with newer versions.

User Participation

It is important for computer user not to become complacent about virus threat after installing antivirus software. They still have to follow safe practices like not copying software from unauthorized sources, checking email attachments, taking regular backups etc. It is required because there may be a time lag between the appearance of a new virus and the remedy for it during which time the files in the computer may get damaged. This is despite the fact most of the antivirus software can detect unusual activity of any yet to be discovered virus and warn the user. But in any case it is better to be safe than sorry.

Other routes of infection

It should be noted that even the read only CDs and DVDs can be harmful as they might have been copied with infected files. Since many of them have Auto run feature, they can infect a computer without any action from the user.

In conclusion, only software from reputed and known sources should be used and safe file sharing should be practiced.