US intelligence officials have said China poses a  persistent threat to US economic and political interests

Cybersecurity investigators noticed a highly unusual software crash - it was affecting a small number of smartphones belonging to people who worked in government, politics, tech and journalism.

The crashes, which began late last year and carried into 2025, were the tipoff to a sophisticated cyberattack that may have allowed hackers to infiltrate a phone without a single click from the user.

The attackers left no clues about their identities, but investigators at the cybersecurity firm iVerify noticed that the victims all had something in common: They worked in fields of interest to China's government and had been targeted by Chinese hackers in the past.

Foreign hackers have increasingly identified smartphones, other mobile devices and the apps they use as a weak link in US cyberdefences. Groups linked to China's military and intelligence service have targeted the smartphones of prominent Americans and burrowed deep into telecommunication networks, according to national security and tech experts.

It shows how vulnerable mobile devices and apps are and the risk that security failures could expose sensitive information or leave American interests open to cyberattack, those experts say.

"The world is in a mobile security crisis right now," said Rocky Cole, a former cybersecurity expert at the National Security Agency and Google and now chief operations officer at iVerify. "No one is watching the phones."

US zeroes in on China as a threat, and Beijing levels its own accusations

US authorities warned in December of a sprawling Chinese hacking campaign designed to gain access to the texts and phone conversations of an unknown number of Americans.

"They were able to listen in on phone calls in real time and able to read text messages," said Rep Raja Krishnamoorthi of Illinois. He is a member of the House Intelligence Committee and the senior Democrat on the Committee on the Chinese Communist Party, created to study the geopolitical threat from China.

Chinese hackers also sought access to phones used by Donald Trump and running mate JD Vance during the 2024 campaign.

The Chinese government has denied allegations of cyberespionage, and accused the US of mounting its own cyberoperations. It says America cites national security as an excuse to issue sanctions against Chinese organizations and keep Chinese technology companies from the global market.

"The US has long been using all kinds of despicable methods to steal other countries' secrets," Lin Jian, a spokesman for China's foreign ministry, said at a recent press conference in response to questions about a CIA push to recruit Chinese informants.

US intelligence officials have said China poses a significant, persistent threat to US economic and political interests.