Hackers in recent weeks have exploited flaws in SharePoint, a document management system developed by Microsoft Corp., to try to steal sensitive data from hundreds of victims.

The company said state-backed hacking groups were breaching systems through flaws in SharePoint, which is used by the U.S. government and companies around the world.

Software giant Microsoft is at the center of cybersecurity storm after China-linked hackers exploited flaws in SharePoint servers to target hundreds of organizations. While such cyberattacks are not new, the scale of the onslaught and the speed with which the hackers took advantage of freshly discovered vulnerabilities is fueling concern.