• 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
  • World's Most Admired Companies
  • See All Rankings
  • Lists Calendar
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
  • Press Center
  • Work At Fortune
  • Terms And Conditions
  • Site Map
  • About Us
  • Press Center
  • Work At Fortune
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

Latest in

Heavy smoke from the Highway 82 Fire in Georgia.
Environmentwildfires
Record heat, zero rain, millions of acres lost: Experts warn wildfires are now America’s problem to survive
By Tristan BoveApril 30, 2026
1 minute ago
gm
North AmericaAutos
GM just boosted its U.S. manufacturing spend to $6 billion in one year—and it may be returning to the idea that made it great
By Nick LichtenbergApril 30, 2026
3 minutes ago
Simple App Review (2026): Expert Tested and Reviewed
Healthmeal delivery
Simple App Review (2026): Expert Tested and Reviewed
By Emily PharesApril 30, 2026
6 minutes ago
hegseth
CommentaryMilitary
America shot its arsenal empty in 2 wars. Now it needs Beijing’s permission to reload
By Steve H. Hanke and David M. WalkerApril 30, 2026
12 minutes ago
Two women look at the backs of two cleaning product packages.
RetailInflation
Your laundry bill is about to get more expensive—and Unilever says the Iran war is partly to blame
By Sasha RogelbergApril 30, 2026
35 minutes ago
AI’s entry-level hiring nightmare is another gift to boomers’ retirement plans
Personal FinancePersonal Finance Evergreen
AI’s entry-level hiring nightmare is another gift to boomers’ retirement plans
By Catherina GioinoApril 30, 2026
38 minutes ago

Most Popular

Apple cofounder Ronald Wayne—whose stake would be worth up to $400 billion had he not sold it in 1976—says that at 91, he has no regrets
Success
Apple cofounder Ronald Wayne—whose stake would be worth up to $400 billion had he not sold it in 1976—says that at 91, he has no regrets
By Preston ForeApril 27, 2026
3 days ago
‘They left me no choice’: Powell isn’t going anywhere—blocking Trump from another Fed appointee
Banking
‘They left me no choice’: Powell isn’t going anywhere—blocking Trump from another Fed appointee
By Eva RoytburgApril 29, 2026
23 hours ago
Jamie Dimon gets candid about national debt: ‘There will be a bond crisis, and then we’ll have to deal with it’
Economy
Jamie Dimon gets candid about national debt: ‘There will be a bond crisis, and then we’ll have to deal with it’
By Eleanor PringleApril 29, 2026
1 day ago
‘The cost of compute is far beyond the costs of the employees’: Nvidia executive says right now AI is more expensive than paying human workers
AI
‘The cost of compute is far beyond the costs of the employees’: Nvidia executive says right now AI is more expensive than paying human workers
By Sasha RogelbergApril 28, 2026
2 days ago
Google Cloud revenue is now 18% of Alphabet's business. Is this the beginning of the end of Google's search identity?
Big Tech
Google Cloud revenue is now 18% of Alphabet's business. Is this the beginning of the end of Google's search identity?
By Alexei OreskovicApril 29, 2026
16 hours ago
‘Take the money and run’: Johns Hopkins economist Steve Hanke on why the UAE quit OPEC
Energy
‘Take the money and run’: Johns Hopkins economist Steve Hanke on why the UAE quit OPEC
By Shawn TullyApril 29, 2026
1 day 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.