Hours after Microsoft revealed hacking groups affiliated with the Chinese government have been exploiting a flaw in its SharePoint software, Bloomberg News reports that the National Nuclear Security Administration has also been breached in the attacks.

The U.S. government agency that maintains and designs America's nuclear weapons was reportedly breached by attackers exploiting zero-day flaws in on-premises

The hackers behind the initial wave of attacks exploiting a zero-day in Microsoft SharePoint servers have so far primarily targeted government organizations, according to researchers and news reports.

The US government agency in charge of designing and maintaining nuclear weapons was among those breached by a hack of Microsoft's SharePoint server software.

Unknown threat actors have reportedly breached the National Nuclear Security Administration's (NNSA) network in attacks exploiting a recently patched Microsoft SharePoint zero-day vulnerability chain.

Microsoft says the Chinese threat actors Linen Typhoon, Violet Typhoon, and Storm-2603 have been exploiting the ToolShell zero-days.

Microsoft has released a critical patch for a security flaw in its SharePoint software. Hackers actively exploited this vulnerability, targeting businesses and US government agencies. The company issued the fix between July 19 and 20.

State CISOs in North Carolina and Arizona said their teams began work immediately to ensure on-prem SharePoint systems were secure, following the recent disclosure of an active zero-day exploit.