When Patching Comes Too Late

China’s Cyber Operatives Breach the U.S. Nuclear Security Agency in a Stark Warning to the West

In a breach that has reignited concerns about the resilience of America’s most sensitive digital infrastructure, Chinese state-sponsored hackers successfully infiltrated the U.S. Department of Energy, including the National Nuclear Security Administration (NNSA), by exploiting a zero-day vulnerability in Microsoft SharePoint. The attack, which unfolded in July 2025, has been attributed to advanced persistent threat groups linked to the People’s Republic of China. These actors, operating under names like Linen Typhoon and Storm-2603, reportedly gained access to internal systems before a patch could be widely deployed.