Microsoft working to fix Exchange Online mailbox quarantine issue
Summary
Microsoft is actively addressing an issue within Exchange Online that has resulted in the incorrect quarantining of customer mailboxes starting Sunday. The company is working to implement a fix to restore normal mailbox functionality.
IFF Assessment
FOE
This incident represents a disruption to a critical business communication service, potentially impacting productivity and requiring security team attention for investigation and remediation.
Defender Context
This issue highlights the importance of monitoring critical infrastructure services for unexpected behavior, even those provided by major vendors. Defenders should be aware of potential service disruptions that could impact email flow and work closely with vendors to understand the scope and resolution timeline.