Microsoft has warned that Chinese state-sponsored hackers have breached its SharePoint software used by the US agency responsible for maintaining and modernizing the nation’s stockpile of nuclear weapons, according to a report.

Researchers say Chinese actors, along with other criminal hackers, exploited a security flaw in SharePoint software widely used by governments and businesses.

After a ProPublica investigation raised security concerns, Microsoft will cease using China-based engineers for work on sensitive Pentagon cloud computing systems.

Some of the most sensitive data the United States has to offer is currently being maintained by engineers from China, often considered, especially in the tech field, its biggest adversary.

A July 8 fix for a critical SharePoint zero-day failed to stop active exploitation, enabling state-backed attackers to breach nearly 100 organizations worldwide.

A series of cyberattacks targeting Microsoft collaboration software, specifically SharePoint, have been linked to Chinese hackers and threat actors.

US President Donald Trump urged tech giants to halt overseas hiring, emphasising job creation at home during an AI Summit. He criticised companies like Google and Microsoft for outsourcing and unveiled new executive orders aimed at reshaping AI infrastructure.

Defense Secretary Pete Hegseth says the DOD is "looking into" a Microsoft cloud program that used Chinese engineers after an investigative report raised concerns about CCP access.