What is the most pricey trojan horse in history?

The most costly trojan horse in history is the Love Bug virus, which was released in 2000. This infection caused an estimated $5.5 billion in damage worldwide, making it the most pricey virus ever. The Love Bug virus was a mass-mailing worm that infected over 45 million computers in simply a couple of days.  https://scarabnet.org/?p=1178 The infection spread quickly by emailing itself to everyone in the victim's address book. As soon as a computer was contaminated, the infection would delete crucial files and spread itself to other computers. The Love Bug infection was ultimately come by a team of anti-virus researchers who created a vaccine that could protect computer systems from the virus.