US Nuclear Weapons Agency Caught up in Microsoft SharePoint Attack

October 8, 2025

INCIDENT

Hours after Microsoft revealed that hacking groups affiliated with the Chinese government have been exploiting a flaw in its SharePoint software, Bloomberg reported that the National Nuclear Security Administration was also breached in the attacks. No sensitive or classified information has leaked according to Bloomberg. “The department was minimally impacted due to its widespread use of the Microsoft M365 cloud. As well as very capable cybersecurity systems,” a department spokesperson said in a statement to Bloomberg. “A very small number of systems were impacted. All impacted systems are being restored.”

Incident Date

July 19, 2025

Estimated Cost


No cost values disclosed.

Type of Malware

No Malware identified

Threat Source

No threat source identified