Chip-maker TSMC has admitted that an outbreak of the WannaCry virus - linked to North Korea - caused the production outage at a number of its production facilities over the weekend.
The company admitted the outbreak in a press conference today, which affected unpatched Windows 7 systems running critical processes in its fabrication facilities.
A frenetic weekend of activity enabled the company to contain the outbreak and to bring it under control, the company claimed.
The company has warned that the incident will cause delays to some shipments and will have a negative impact on its third-quarter results.
TSMC is manufacturing the Apple-designed microprocessors for the next iPhone, which is expected to be launched next month, but analysts don't expect production of that - or any of Apple's other forthcoming new devices - to be affected.
The company claims that it will make-up the production losses in the fourth quarter.
In a statement released yesterday, the company said: "The degree of infection varied by fab. TSMC contained the problem and found a solution. As of 14:00 Taiwan time [on Sunday], about 80 per cent of the company's impacted tools have been recovered, and the company expects full recovery on 6 August.
"TSMC expects this incident to cause shipment delays and additional costs. We estimate the impact to third quarter revenue to be about three percent, and impact to gross margin to be about one percentage point.
"The company is confident shipments delayed in third quarter will be recovered in the fourth quarter 2018, and maintains its forecast… Most of TSMC's customers have been notified of this event, and the company is working closely with customers on their wafer delivery schedule."
It's not entirely clear how the virus was able to penetrate the company's systems, with TSMC's own explanation not being entirely clear.
The statement concluded: "This virus outbreak occurred due to mis-operation during the software installation process for a new tool, which caused a virus to spread once the tool was connected to the Company's computer network.
"Data integrity and confidential information was not compromised. TSMC has taken actions to close this security gap and further strengthen security measures."
TSMC has been the target of alleged industrial espionage from well-funded semiconductor companies in China for more than a decade.
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