Japanese chip-testing giant Advantest has disclosed that personal data was stolen in a ransomware attack it suffered months ago.
The company said Social Security numbers, passport details and other personal information were taken in the February intrusion, and that more than 500 California residents have been notified.
According to cybersecurity reports, the breach was claimed by a ransomware group, and the months-long gap between the attack and the disclosure is likely to draw scrutiny from regulators.
Advantest is a key supplier of testing equipment to the world’s biggest chipmakers, making the incident the latest reminder of how cyberattacks can reach deep into the semiconductor supply chain.
The company said it has hardened its systems since the attack and is cooperating with authorities as investigations continue.
The disclosure lands amid a wave of ransomware incidents targeting industrial and technology firms, whose operational data and intellectual property make them lucrative targets.
Security experts say the theft of passport and Social Security data is particularly serious, since such information can fuel identity fraud for years. Affected individuals are typically offered credit monitoring, though experts caution that vigilance matters more.
For the chip industry, the episode is another warning that cybersecurity is now a supply-chain issue: a breach at a testing-equipment maker can ripple outward to the fabs and customers that depend on it.
Japan’s data-breach notification rules, like those in California, require companies to inform affected residents when personal information is compromised. The notices to more than 500 Californians suggest the breach touched the company’s American operations.
Ransomware groups have increasingly targeted technology manufacturers, betting that the pressure to keep production lines running will force quick payments. Advantest has not said whether a ransom was paid.
The incident also raises questions about disclosure timelines. Months elapsed between the February attack and this week’s announcement — a gap regulators in multiple jurisdictions are likely to examine.
As the investigation continues, the company’s customers — some of the biggest names in chips — will be watching closely for any sign that the breach extended beyond personal data into trade secrets.
