Microsoft says Chinese hackers accessed 25 organizations, including governments
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Microsoft (NASDAQ:MSFT) said late on Tuesday that China-based hackers illegally accessed the email accounts of roughly 25 organizations, including several government agencies.
The hackers, known as Storm-0558, illegally forged authentication tokens to access user email from an acquired Microsoft account consumer signing key. The activity started on May 15 and continued.
Microsoft (MSFT) added that it had successfully blocked Storm-0558 from accessing customer email and that no customer action is required. The Redmond, Washington-based tech giant added that it had contacted all organizations directly to provide them with information on how to respond and investigate. 
In a separate blog post, Microsoft (MSFT) executive vice president of security Charlie Bell said cyber attacks are continuing to increase in both sophistication and frequency.
"These well-resourced adversaries draw no distinction between trying to compromise business or personal accounts associated with targeted organizations, since it only takes one successfully compromised account login to gain persistent access, exfiltrate information and achieve espionage objectives," Bell wrote. 
"We assess this adversary is focused on espionage, such as gaining access to email systems for intelligence collection. This type of espionage-motivated adversary seeks to abuse credentials and gain access to data residing in sensitive systems," Bell added. 
Microsoft (MSFT) did not say which organizations had been impacted, however, U.S. National Security Advisor Jake Sullivan told ABC News on Wednesday that the breach had been detected "fairly rapidly." 
Sullivan added that further breaches were prevented.
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