Security News > 2023 > July > Chinese hackers forged authentication tokens to breach government emails

Sophisticated hackers have accessed email accounts of organizations and government agencies via authentication tokens they forged by using an acquired Microsoft account consumer signing key, the company has revealed on Tuesday.

"The threat actor Microsoft links to this incident is an adversary based in China that Microsoft calls Storm-0558. We assess this adversary is focused on espionage, such as gaining access to email systems for intelligence collection."

Microsoft began investigating anomalous mail activity on June 16, 2023, after being alerted by customers.

"We have no indications that Azure AD keys or any other MSA keys were used by this actor. OWA and Outlook.com are the only services where we have observed the actor using tokens forged with the acquired MSA key."

Microsoft says customers don't have to do anything to protect themselves against this attack - the company has implemented mitigations.

Microsoft has also shared on Tuesday that attackers have been exploiting its Microsoft Windows Hardware Developer Program to sign malicious drivers, and has released fixes for various zero-days actively exploited in the wild.

News URL

https://www.helpnetsecurity.com/2023/07/12/storm-0558-forged-authentication-tokens/