• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
China

China government hackers worked for months to infiltrate Microsoft accounts for U.S. officials—and succeeded

By
Frank Bajak
Frank Bajak
,
Matthew Lee
Matthew Lee
, and
The Associated Press
The Associated Press
Down Arrow Button Icon
By
Frank Bajak
Frank Bajak
,
Matthew Lee
Matthew Lee
, and
The Associated Press
The Associated Press
Down Arrow Button Icon
July 12, 2023, 6:09 PM ET
Microsoft
A presenter talks about Microsoft in the Information Age during the World Artificial Intelligence Conference in Shanghai, Thursday, July 6, 2023. AP Photo/Ng Han Guan

State-backed Chinese hackers foiled Microsoft’s cloud-based security in hacking the email accounts of officials at multiple U.S. agencies that deal with China ahead of Secretary of State Antony Blinken’s trip to Beijing last month, officials said Wednesday.

Recommended Video

The surgical, targeted espionage accessed the email of a small number of individuals at an unspecified number of U.S. agencies and was discovered in mid-June by the State Department, U.S. officials said. They said none of the breached systems were classified, nor was any of the stolen data.

One person familiar with the investigation said U.S. military and intelligence agencies were not among the agencies impacted in the monthlong spying campaign, which also affected unnamed foreign governments.

The officials spoke on condition they not be further identified.

In a technical advisory Wednesday and a call with reporters, the U.S. Cybersecurity and Infrastructure Security Agency and the FBI said Microsoft determined the hackers gained access by impersonating authorized users.

Officials did not specify the nature of the stolen data. But one U.S. official said the intrusion was “directly targeted” at diplomats and others who deal with the China portfolio at the State Department and other agencies. The official added that it was not yet clear if there had been any significant compromise of information.

The Blinken trip went ahead as planned, although with customary information security procedures in place, which required his delegation to use “burner” phones and computers in China.

The hack was disclosed late Tuesday by Microsoft in a blog post. It said it was alerted to the breach, which it blamed on a state-backed, espionage-focused Chinese hacking group “known to target government agencies in Western Europe,” on June 16. Microsoft said the group, which it calls Storm-0558, had gained access to email accounts affecting about 25 organizations, including government agencies, since mid-May as well as to consumer accounts of individuals likely associated with those agencies.

Neither Microsoft nor U.S. officials would identify the agencies or governments impacted. But a senior CISA official told reporters in a press call that just a handful of those organizations are in the United States.

While the official declined to say whether U.S. officials are displeased with Microsoft over the breach, U.S. National Security Council spokesman Adam Hodge noted that it was “government safeguards” that detected the intrusion and added, “We continue to hold the procurement providers of the U.S. Government to a high security threshold.”

In fact, those safeguards consist of a data-logging feature for which Microsoft charges a premium. The CISA official noted that some of the victims lacked the data-logging feature and, unable to detect the breach, learned of it from Microsoft.

The Storm-0558 hackers broke in using forged authentication tokens — data used to verify the identity of a user — to access the email accounts, Microsoft said.

Cybersecurity researcher Jake Williams, a former National Security Agency offensive hacker, said it remains unclear how the hackers accomplished that. But he was concerned that forged tokens could have been widely used against any number of different Microsoft users.

“I can’t imagine China didn’t also use this access to target dissidents on personal subscriptions, too,” he said.

A Chinese foreign ministry spokesman, Wang Wenbin, called the U.S. accusation of hacking “disinformation” aimed at diverting attention from U.S. cyberespionage against China.

“No matter which agency issued this information, it will never change the fact that the United States is the world’s largest hacker empire conducting the most cyber theft,” Wang said in a routine briefing.

U.S. intelligence agencies also use hacking as a critical espionage tool and it is not a violation of international law.

Some U.S. officials accuse Beijing of going too far with its state-sponsored hacking. China’s long-standing campaign of hacking for geopolitical advantage had included the massive theft of U.S., and allied intellectual property and U.S. government personnel records.

On Wednesday, Senate intelligence committee chair Mark Warner issued a statement saying the latest Chinese breach shows Beijing is “steadily improving its cyber collection capabilities directed against the U.S. and our allies.”

Last month, Google-owned cybersecurity firm Mandiant said suspected state-backed Chinese hackers broke into the networks of hundreds of public and private sector organizations globally exploiting a vulnerability in a popular email security tool.

Earlier this year, Microsoft said state-backed Chinese hackers were targeting U.S. critical infrastructure and could be laying the technical groundwork to disrupt critical communications between the U.S. and Asia during future crises.

____

Associated Press writers Aamer Madhani in Washington and Zen Soo in Hong Kong contributed to this report. Bajak reported from Boston.

Join us at the Fortune Workplace Innovation Summit May 19–20, 2026, in Atlanta. The next era of workplace innovation is here—and the old playbook is being rewritten. At this exclusive, high-energy event, the world’s most innovative leaders will convene to explore how AI, humanity, and strategy converge to redefine, again, the future of work. Register now.
About the Authors
By Frank Bajak
See full bioRight Arrow Button Icon
By Matthew Lee
See full bioRight Arrow Button Icon
By The Associated Press
See full bioRight Arrow Button Icon

Latest in

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
  • Group Subscriptions
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

Latest in

 The world’s 500 richest people made more than a quarter trillion yesterday as volatile markets react to fragile Iran war ceasefire
EconomyBillionaires
 The world’s 500 richest people made more than a quarter trillion yesterday as volatile markets react to fragile Iran war ceasefire
By Jacqueline MunisApril 9, 2026
9 hours ago
Only five ships crossed the Strait of Hormuz Thursday, far below Iran’s pledge as negotiations begin
EnergyIran
Only five ships crossed the Strait of Hormuz Thursday, far below Iran’s pledge as negotiations begin
By Eva RoytburgApril 9, 2026
11 hours ago
7 best debt relief companies 2026
Personal FinanceLoans
7 best debt relief companies 2026
By Joseph HostetlerApril 9, 2026
12 hours ago
JFK, jr and Carolyn Bessette walk their dog in New York City.
RetailLevi Strauss
Levi’s 517 jeans sales jump 25% thanks to ‘Love Story’ and the Carolyn Bessette Kennedy effect
By Molly Liebergall and Morning BrewApril 9, 2026
12 hours ago
iran
EnergyFood and drink
A global food emergency: Why the closed Strait of Hormuz puts half the world’s calories at risk
By Aya S. Chacar and The ConversationApril 9, 2026
14 hours ago
Willie Walsh, wearing a blue suit, looks to his right with his mouth slightly open.
EnergyAviation
Jet fuel supply disruptions are comparable to 9/11 and could take months to replenish even if Hormuz Strait is reopening, airline trade group warns
By Sasha RogelbergApril 9, 2026
14 hours ago

Most Popular

The U.S. government is spending $88 billion a month in interest on national debt—equal to spending on defense and education combined
Economy
The U.S. government is spending $88 billion a month in interest on national debt—equal to spending on defense and education combined
By Fortune EditorsApril 9, 2026
19 hours ago
A Meta employee created a dashboard so coworkers can compete to be the company's No. 1 AI token user—and Zuckerberg doesn't even rank in the top 250
AI
A Meta employee created a dashboard so coworkers can compete to be the company's No. 1 AI token user—and Zuckerberg doesn't even rank in the top 250
By Fortune EditorsApril 9, 2026
22 hours ago
Gen Z doesn't want your full-time job. They want several part-time roles, and it's reshaping the entire workforce
Success
Gen Z doesn't want your full-time job. They want several part-time roles, and it's reshaping the entire workforce
By Fortune EditorsApril 9, 2026
23 hours ago
White-collar workers are quietly rebelling against AI as 80% outright refuse adoption mandates
AI
White-collar workers are quietly rebelling against AI as 80% outright refuse adoption mandates
By Fortune EditorsApril 9, 2026
20 hours ago
2 years ago, Saudi Arabia quietly canceled the ‘petrodollar’ deal with America that wired the world economy for 50 years. Then war broke out in Iran
Energy
2 years ago, Saudi Arabia quietly canceled the ‘petrodollar’ deal with America that wired the world economy for 50 years. Then war broke out in Iran
By Fortune EditorsApril 7, 2026
2 days ago
Gen Z workers are so fearful AI will take their job they’re intentionally sabotaging their company’s AI rollout
AI
Gen Z workers are so fearful AI will take their job they’re intentionally sabotaging their company’s AI rollout
By Fortune EditorsApril 8, 2026
2 days ago

© 2026 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.