Japan’s Ground Self-Defense Force has unknowingly used USB flash drives infected with malware linked by cybersecurity researchers to Chinese hacking groups for nearly a year, according to an investigation by the Japanese newspaper Nikkei Asia.
The issue came to light after a computer malfunction at a regional command in Itami, western Japan, triggered an internal investigation.
Authorities identified six compromised USB drives that had been connected to more than 50 of 480 computers examined.
According to the report, nearly half of the affected systems were connected to closed networks used to handle highly sensitive information, including command-and-control data.
Investigators concluded that the devices were counterfeit USB drives manufactured in China.
A Ground Self-Defense Force official said several control systems stopped functioning as a result of the incident.
The Self-Defense Forces said, however, that they found no evidence of system compromise or leakage of sensitive information, and added that antivirus screening procedures have since been strengthened.
Counterfeit USB Drives
The drives had reportedly been supplied in March 2024 for disaster relief operations following the Noto Peninsula earthquake.
Although marketed as 1-terabyte storage devices, investigators found they actually contained 240-gigabyte microSD cards, and some had reportedly been preloaded with malware before use.
Despite multiple antivirus screening procedures, the devices were not scanned before deployment, allowing the malware to remain undetected.
According to the report, US cybersecurity companies have previously linked the malware to Chinese threat actors and said it is designed to execute automatically when a USB drive is inserted into a computer.
Rising Tensions
The news comes amid renewed tensions between Tokyo and Beijing.
Earlier this month, Japan rejected Chinese accusations that its military had harassed a Chinese aircraft carrier strike group during a 40-day deployment in the Pacific.
Beijing claimed Japanese ships and aircraft repeatedly tracked and monitored the formation at close range as the Liaoning carrier group conducted day-and-night exercises across the South China Sea and the Western Pacific.
Bilateral relations have also remained strained over regional security issues, including Taiwan, after Prime Minister Sanae Takaichi said last year Japan could intervene militarily in the event of a Chinese attack on the island.
