📅 April 26, 1999
On April 26, 1999, millions of Windows computers around the world were crippled by a virus timed to strike with precision and malice.
Known as the CIH virus—and nicknamed "Chernobyl"—this piece of malicious code activated on the 13th anniversary of the Chernobyl nuclear disaster. While it didn’t cause physical harm like its namesake, it delivered devastating consequences for digital systems.
Created in 1998 by a Taiwanese university student, Chen Ing-hau, the CIH virus infected Windows 95, 98, and ME systems. It spread silently via infected software, often pirated or distributed through CDs—a major method of software delivery at the time.
Once activated, CIH could do two types of damage:
Overwrite the first megabyte of the hard drive, rendering data unrecoverable and operating systems unbootable.
Attempt to corrupt the computer’s BIOS, which could leave machines completely inoperable without physical repairs or replacement.
It’s estimated that over 60 million computers were affected globally, causing hundreds of millions of dollars in damages.
CIH was a wake-up call for the software industry, hardware manufacturers, and users alike. It highlighted:
The vulnerability of BIOS-level firmware
The lack of built-in protections in older Windows systems
The dangers of unchecked software distribution
It also accelerated the adoption of antivirus software and better firmware protections in PCs.
Despite the scale of damage, Chen Ing-hau wasn’t prosecuted due to Taiwan’s lack of cybercrime laws at the time.
CIH is one of the rare viruses capable of causing hardware-level damage, though actual BIOS corruption was less common than hard drive destruction.
The name “Chernobyl” was coined by media outlets because of the activation date, not the virus’s origin.
CIH is a stark reminder of how one overlooked vulnerability can shut down an entire operation.
At GAM Tech, we believe in being proactive, not reactive. Our cybersecurity services include endpoint protection, dark web monitoring, and patch management that ensure threats like this don’t get through the cracks.
Cyber threats have only grown more sophisticated since 1999. But so have we. Let’s make sure your business is ready for whatever’s next.