Chinese hackers breach US government emails in targeted Microsoft attack

Chinese hackers exploited a vulnerability in Microsoft's email system to access accounts across US government agencies and organizations in Europe.
The hackers were identified as Storm-0558, a China-based group focused on espionage and data theft targeting Western governments.
Email accounts at around 25 organizations were compromised over the course of a month before the breach was detected in mid-June.
No classified information or sensitive data was obtained, but the hack raises concerns over US-China relations and cloud security.
Microsoft has mitigated the attack by blocking the forged authentication tokens used by the hackers to impersonate authorized users.