Microsoft mitigates China-based threat actor Storm-0558 targeting of customer email

Source: https://msrc.microsoft.com/blog/2023/07/microsoft-mitigates-china-based-threat-actor-storm-0558-targeting-of-customer-email/

UPDATE: Microsoft has released threat analysis on Storm-0558 activity here. Microsoft additionally released additional defense-in-depth security fixes to help customers improve token validation in their custom applications.
Microsoft has mitigated an attack by a China-based threat actor Microsoft tracks as Storm-0558 which targeted customer emails. Storm-0558 primarily targets government agencies in Western Europe and focuses on espionage, data theft, and credential access.

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