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.

Microsoft has announced a critical SharePoint server breach affecting thousands of systems, prompting global cybersecurity efforts and emergency fixes.

A global cyberattack is unfolding as hackers exploit a critical zero-day vulnerability in Microsoft's SharePoint software, threatening tens of thousands of on-premises servers used by