O365 Suspicious Email Behavior Alert

This analytic identifies when built-in Microsoft 365 security detections for suspicious email behaviors are triggered. These alerts often indicate that an attacker may have compromised a mailbox within the environment, leading to activities such as suspicious email sending patterns, user restrictions from sending email, suspicious email forwarding activity, or email sending limits being exceeded. Monitoring these alerts is crucial for responding to potential account compromises and malicious email activities.