The Love Bug — How a 26-Year-Old Created One of the World’s Most Destructive Computer Viruses

May 11, 2024

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The Love Bug computer virus is considered one of the most destructive of all time. It eventually spread to more than 10 million personal computers and caused billions of dollars of damage worldwide. Unknowing victims were duped by a fake “love letter,” which released the virus to anyone they were connecting with, and the creator of the virus had no idea how far his creation would eventually spread across the world.

The Love Bug virus, also known as the ILOVEYOU virus, began infecting computers on May 4, 2000. The virus was simple but very destructive. When a user’s files were infected, they were overwritten with copies of the virus. This caused users to reinfect their system whenever they tried to open a file. The virus also attempted to steal a user’s passwords.

The virus spread by causing a victim’s computer to email everyone they had in their Microsoft Outlook contacts list. The email had a subject line saying “ILOVEYOU’, and the body read, “kindly check the attached love letter coming from me.” A text file with the title “love-letter-for-you” contained a copy of the virus.

Before long, the virus had infected computers around the world after curious users opened the text file. Estimates for damage done by the virus were anywhere from $5 billion to $20 billion. Much of the cost came from fixing computers and ensuring they didn’t get infected again.

Investigators began trying to trace the source of the virus and found that stolen passwords were being sent to an email address in Manila, Philippines. Philippine police traced the address to an apartment in Manila, and a 23-year-old computer science student at AMA Computer College named Onel de Guzman. Investigators also discovered a hacking group of AMA students existed, with one member being de Guzman, who had been experimenting with computer viruses. Investigators had come across the phrase “grammersoft” in the virus, which was the hacking group’s name.

De Guzman obtained a lawyer who then called a press conference and answered questions from the media. De Guzman only responded to one question when asked if he possibly released the virus accidentally. He replied, “It is possible.”

That became the only explanation for releasing the virus because de Guzman was never prosecuted for the crime. The Philippines had no laws against computer hacking or releasing a computer virus. There was some suspicion that a friend from de Guzman’s school, Michael Buen, also had a hand in the Love Bug virus. Though he denied it, some sources listed his name beside de Guzman as the creator.

In an interview with WIRED, 20 years after releasing the virus, de Guzman said he never expected the virus to reach Europe or the US and that the Love Bug wasn’t a virus but a Trojan horse, a type of malware that downloads onto a computer disguised as a legitimate program. De Guzman stated that since he was poor and internet access was expensive, he planned to steal passwords from those who had paid for it so he could use the internet. He told WIRED that designing the software wasn’t difficult because of “a bug in Windows 95.”

De Guzman experimented in internet chat rooms in Manila, where he sent victims an infected file with a picture of himself. The virus worked, but de Guzman wanted to move outside of Manila since, at the time, he was only able to steal dial-up passwords for phones in the Philippines.

In May 2000, he changed the virus code so it wouldn’t be limited to those computers in Manila. He also programmed the virus to infect a computer and send a copy to anyone in the user’s Outlook address list. His other tactic, which made the curious tempted to open the attachment, was giving the title a subject that had universal appeal: a fake love letter. Once the virus began to spread, de Guzman had no control over it.

De Guzman’s mother was the first to inform him that the search was on for a hacker in Manila. She knew that de Guzman was engaging in hacking and hid his computer, but he had left a disk in the home containing another virus, one Michael Buen had worked on. This is what had connected Buen to the Love Bug. In the interview with WIRED, de Guzman stated that his classmate had nothing to do with the Love Bug and that he created it all on his own.

De Guzman never graduated from college and didn’t even return to the school after being accused. He stated he regretted making the virus and hadn’t touched a computer for a year. He became a mobile phone technician and ended up having two children, but he will always be known as the creator of one of the most destructive computer viruses ever.

Source: Wired, HP, CNN, BBC

About the author 

Daniel Ganninger - The writer, editor, and chief lackey of Knowledge Stew, the author of the Knowledge Stew line of trivia books, and editor of Fact World and the Knowledge Stew sister site on Medium, our ad-free subscription sites. I hope you learn many new things here that add to your knowledge.

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