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Chinese state-backed hackers breach US nuclear agency

Jul 23, 2025, 6:31am EDT
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An illustration of a Chinese hacker.
Bill Hinton/Getty Images

Chinese state-backed hackers broke into a US agency which designs nuclear weapons, Microsoft said.

The tech giant said hacking groups exploited security flaws to access Microsoft document-sharing software used by the National Nuclear Security Administration; other government agencies were also hacked. China denied involvement and called the accusations “smearing.”

Cyberattacks, both state-sponsored and private, are a growing problem: British institutions are to be banned from paying ransom money to hackers after a spate of Russia-aligned attacks, Politico reported. One 158-year-old British transportation firm had to shut down altogether after hackers guessed one employee’s weak password, locked down its systems, and demanded a ransom the firm was unable to pay.

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