O365 New Forwarding Mailflow Rule Created

This rule detects the creation of new mail flow rules in Office 365 that are configured to redirect or copy emails to unauthorized or external addresses. It specifically looks for the "New-TransportRule" operation in Office 365 Management Activity logs, combined with parameters such as "BlindCopyTo", "CopyTo", or "RedirectMessageTo". Such activity can indicate potential data exfiltration, unauthorized access to sensitive information, or an attacker attempting to intercept email communications, which could lead to data breaches or information leakage.