Onel de Guzman

In May 2000, a computer worm known as the ‘love bug’ attacked millions of computers across the globe, causing an estimated billions of dollars worth of damage.

Early one morning on 4th May, a string of emails began circulating South East Asia, quickly spreading to Europe and finally the United States. This was an email entitled “I Love You”, complete with an apparent love letter attached. When the recipient curiously opened this attached file, a seemingly innocuous text file would be opened, actually running an executable file which released the Love Bug worm.

The worm was written in Visual Basic Script, a relatively simple piece of code which exploited a weakness in the design of Microsoft Windows, allowing it to alter and overwrite random files on the victim’s computer, rendering it unbootable. In addition to this it would send a copy of itself to every contact in the recipient’s address book. The curiously entitled email successfully enticed millions of users into opening the attachment, assuming it was safe as the email typically appeared to be from a friend or colleague, ensuring the propagation of the worm. Furthermore, at this point in time people were far less likely to have appropriate anti-virus software installed on their computers and were generally less aware of the warning signs of such cyber attacks.

It was quickly established that the message had originated in Manila in the Philippines. After scrutinising the code, which was entirely visible due to it being written in Visual Basic, it became clear that data sent by the worm was being forwarded to two Filipino email addresses. Philippines’ National Bureau of Investigation (NBI) traced the programme back to an apartment belonging to 27-year-old Reonel Ramones. However it soon became apparent that Ramones could not have been responsible for the creation and release of the Love Bug, and suspicion quickly fell on his friend and fellow programmer 23-year-old Onel de Guzman.

Seeking further evidence, the NBI investigated AMA Computer College where, up until recently, de Guzman had been an undergraduate student. Upon speaking with his professor, it transpired that de Guzman had proposed the creation of a trojan to steal internet login passwords as his undergraduate thesis, which of course was rejected by the college’s board. Soon after this de Guzman dropped out of college.

Unfortunately at the time, there were no laws against writing malware, and so de Guzman was released and all charges were dropped. Two months later the relevant legislation was brought into power.


BBC News. A decade on from the ILOVEYOU bug. [online] Available:

Naked Security. Memories of the Love Bug worm. [online] Available:

Santanam, R. Vidyapeetham, A. Virendra, M (2011). Cyber Security, Cyber Crime and Cyber Forensics: Applications and Perspectives. Information Science Reference: Hershey PA.