Sophos analysis shows mass-mailing viruses pose greatest
A report published by Sophos, the world leader in network-based
anti-virus solutions, of the most commonly reported computer
viruses throughout 1999 shows that virus writers are taking
advantage of the Internet and corporate email systems to distribute
their creations more quickly.
The analysis highlights three self-propagating viruses in the
Top Ten. WM97/Melissa, W32/ExploreZip
forward themselves via email attachments to unsuspecting computer
users. Instead of taking months to spread into the wild, these
viruses have the potential to attack globally within days.
"Whilst we have seen a proliferation of new viruses, these
results show that companies are still commonly infected by old
viruses, despite the media focusing on new threats," said Graham
Cluley, senior technology consultant for Sophos. "For example,
Sophos statistics show that the most frequently reported virus of
1999 was XM/Laroux,
a macro virus that infects spreadsheets, first seen in 1996.
Meanwhile, the Form
boot sector virus also appears in the Top Ten, despite being first
seen almost 10 years ago. As always, we recommend that businesses
keep their anti-virus software up-to-date and employ 'safe-computing'
Other developments in 1999 included:
- David L Smith pleaded guilty to
distributing the Melissa macro virus, and admitted causing more
than 80 million dollars damage to North American companies.
Sentencing is expected in February 2000.
- Asia Pacific was hit hard in April by W95/CIH-10xx, the first
PC-paralysing virus that flashed computer BIOSes. Fortunately,
Western companies had listened to anti-virus vendor warnings and
had largely put protection in place.
- An Internet hoax that claimed a
game, which featured Santa Claus knocking down elves with a ten-pin
bowling ball, was infected by a virus fooled millions of computer
users. Paranoid users panicked that they may have unintentionally
infected their company networks - but in fact the game was
- The Bubbleboy worm
threatened to break all the rules by being the first virus to
execute itself as soon as a recipient's email is opened, rather
than needing any attachment to be opened. This was only possible
because of a security loophole in Microsoft Outlook, which many
users quickly patched.
To view the Sophos top ten, please click here