Viruses Tag Along
If there's one thing that anti-virus software makers fear—aside from a mass change of heart by the virus writers—it's the creation of a virus-delivery mechanism that evades detection by their signature-based products. The development of detection files for every new virus is the meat and potatoes of what anti-virus vendors do. Because each virus is unique, anti-virus products require new signatures to detect each one, even those that are simply variants of previous malware. Without the signatures, anti-virus software is essentially blind: Not only won't it be able to stop the virus, but it also won't even be able to alert the user that a virus may have come through.
