China-Linked Hackers Breach US Nuclear Weapons Agency In Sophisticated Operation

The NNSA, responsible for nuclear reactor production and arsenal maintenance, suffered a serious cyberattack exploiting a zero-day vulnerability in on-premises Microsoft SharePoint. Hackers, suspected to be linked to the Chinese government, targeted SharePoint Server 2019 and Subscription Edition. This advanced remote code execution attack allowed attackers to bypass security, steal data, and potentially move deeper into connected networks. The Department of Energy stated that a minimal number of systems were affected and no classified data was compromised. The agency's early adoption of Microsoft 365 cloud services mitigated the impact, as the vulnerability was limited to on-premises systems. Microsoft is investigating the breaches, expecting further exploitation of the vulnerability. Other governments in Canada, Brazil, Spain, Indonesia, South Africa, the United Kingdom, and Switzerland are also reported to be targeted. China denies any involvement, calling the allegations "unfounded speculation." The US is taking swift defensive cyber-action due to the sensitive nature of the breached technology and China's alleged involvement.