deadly computer viruses

Damaging the computer through network ports, Sasser mostly targeted Windows 2000 and XP. Its main casualties were the news agency Agence France Presse (AFP) which had all its satellite communications jammed for hours , U.S. Airlines which had to reschedule its flights because of the worm had depleted their computers, a Finnish insurance company which was forced to close down 130 of its offices on emergency basis, Goldman Sachs, and Deutsche Post were all badly affected as well. However its unique feature was that it did not spread through emails, but rather observed computers and kept a look out for their vulnerabilities. On the basis of its knowledge, it would scan random IP addresses from the database and send itself to the next victim.