Up One Level



A virus is a form of malicious code and, as such it is potentially disruptive. It may also be transferred unknowingly from one computer to another. The term Virus includes all sort of variations on a theme, including the nastier variants of macro-viruses, Trojans, and Worms, but, for convenience, all such programs are classed simply as 'virus'.

Viruses are a very real problem for both organisation and individual computer users. At the present time there are very few, if any, virus which affect large computers, primarily because the programming languages which those systems use are not the same as those used to write virus code. Viruses, therefore are a problem primarily for users of PCs and servers.

As at January 2001, there were over 48,000 known viruses. Fortunately the great majority of these are classed as 'rare' and usually appear only in virus research centre files. However, that still leaves nearly 5,000 viruses, classed as 'common', roaming the world's computer networks, so there is absolutely no room for complacency.

They tend to fall into 3 groups:-

Dangerous; - such as 'Resume' and 'Loveletter' which do real, sometimes irrevocable, damage to a computer's system files, and the programs and data held on the computer's storage media, as well as attempting to steal and transmit user ID and password information

Childish; - such as 'Yeke', 'Hitchcock', 'Flip', and Diamond, which do not, generally, corrupt or destroy data, programs, or boot records, but restrict themselves to irritating activities such as displaying childish messages, playing sounds, flipping the screen upside down, or displaying animated graphics

Ineffective - those, such as 'Bleah', which appear to do nothing at all except reproduce themselves, or attach themselves to files in the system, thereby clogging up the storage media with unnecessary clutter. Some of these viruses are ineffective because of badly written code, - they should do something, but the virus writer didn't get it quite right.

Within all types there are some which operate on the basis of a 'triggered event' usually a date such as April 1st, or October 31st, or a time such 15:10 each day when the 'Tea Time' virus activates.

Organisations should maintain a 'virus diary' of known high risk dates/times to ensure that anti-virus measures are in place as required.

*** The Information Security Glossary ***
Previous PageTop of this pageNext Page

Buy Now:


This Glossary forms part of the RUsecure Security Policy Suite... visit RUsecure Security Policy World
Use of the guidance contained within RUsecure™ is subject to the End User Licence Agreement
This site created with EasyHTMLHelp(tm) for MS Word
 Risk Associates: Resources for Security Risk Analysis, ISO 17799 / BS7799, Security Policies and Security Audit