Senators Want Details on China’s Latest Hack of Microsoft email

Senators want answers from the State Department’s IT chief about how hackers, said to be from China, broke into diplomats’ Microsoft email accounts earlier this year, as officials were planning high stakes visits to Beijing for Secretary of State Anthony Blinken and other cabinet officials.

In a letter sent Wednesday to State Department Chief Information Officer Kelly Fletcher, and exclusively obtained by Newsweek, 14 senators of both parties are asking for details of the extent of the breach, and the timeline on which it was fixed.

Microsoft revealed on July 11 that hackers had “acquired” a master cryptographic key, which allowed them to impersonate almost any user of the company’s cloud-based Outlook email and calendar services, meaning they could log on as that person and copy all their email traffic and calendar appointments.

The letter, originally drafted by Sen. Eric Schmitt, R-Mo., was signed by GOP colleagues including Tim Scott of Florida and Bill Hagerty of Tennessee; and by the Democratic Chairman of the Senate Foreign Relations Commitee Ben Cardin of Maryland and several of his colleagues including Tim Kaine of Virginia. It asks for a “closed, unclassified briefing” for members and staff by September 6.

The intrusion, which started mid-May and was discovered a month later, would have allowed Beijing to see into diplomats’ planning for a succession of high stakes visits to China in June and July by U.S. cabinet members, including Blinken, Commerce Secretary Gina Raimondi and Treasury Secretary Janet Yellen, according to former officials.

The hack has led to questions about Microsoft’s relationship with China and whether that creates risks for the U.S. government, which relies heavily on the Redmond, Wash.-based tech giant’s services and products.

The senators’ letter also asks Fletcher to explain how she plans to “ensure a more robust,…