Microchip Technology said on Tuesday an «unauthorized party» disrupted the company's use of certain servers and some business operations.
After detecting «potentially suspicious activity» in its IT systems on Saturday, the chipmaker began taking steps to assess and contain the issue, it said in a filing.
Shares of the company were down about 3% in extended trading.
Microchip said its manufacturing facilities were operating at less-than-normal levels and its ability to fulfill orders was impacted.
The company has shut down certain systems and launched an investigation with the assistance of external cybersecurity advisers.