After 33 years, Bernardo Quintero decided it was time to find the person who changed his life — the anonymous programmer who created a computer virus that had infected his university decades earlier.

The virus, called Virus Málaga, was mostly harmless. But the challenge of defeating it sparked Quintero’s passion for cybersecurity, eventually leading him to found VirusTotal, a startup that Google acquired in 2012. That acquisition brought Google’s flagship European cybersecurity center to Málaga, transforming the Spanish city into a tech hub.

All because of a small malware program created by someone whose identity Quintero had never known. Moved by nostalgia and gratitude, Quintero launched a search earlier this year. He asked Spanish media outlets to amplify his quest for tips. He dove back into the virus’s code, looking for clues his 18-year-old self might have missed. And he eventually solved the mystery, sharing the bittersweet resolution in a LinkedIn post that went viral.

The story begins in 1992, when a young Quintero was prompted by a teacher to create an antivirus for the 2610-byte program that had spread across the computers of Málaga’s Polytechnic School. “That challenge in my first year at university sparked a deep interest in computer viruses and security, and without it my path might have been very different,” Quintero told TechCrunch.

Quintero’s search was aided by his programmer instincts. Earlier this year, he stepped down from his team manager role to “go back to the cave, to the basement of Google.” He didn’t leave the company; instead, he went back to tinkering and experimenting without managerial duties.

That tinkering mindset also led him to reexamine Virus Málaga and look for details he’d missed years earlier. First, he found fragments of a signature, but thanks to another security expert, he discovered a later variant of the virus with a much clearer cue: “KIKESOYYO.” “Kike soy yo” would translate to “I am Kike,” a common nickname for “Enrique.” 

Around the same time, Quintero received a direct message from a man who is now the general digital transformation coordinator for the Spanish city of Cordoba and who claimed he witnessed one of his Polytechnic School classmates create the virus. Many details added up, but one stood out in particular: The man knew that the virus’s hidden message — called a payload, in cybersecurity terms — was a statement condemning the Basque terrorist group ETA, a fact that Quintero had never disclosed.