TSMC, the largest semiconductor manufacturer in the world, lost an entire day of production after its factories systems were halted by a computer virus in early August. This is the first time that a virus has affected TSMC’s production lines.

TMSC said “This virus outbreak occurred due to misoperation 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 builds chips for Apple’s iPhones including the A11 processor that is in the iPhone X. They are also currently producing the A12 processor that is expected to be used in Apple’s new models. TSMC also builds chips for AMD, NVIDIA and Qualcomm.