Unauthorised Email Preview or Download by Microsoft 365 Admin/User
In Microsoft 365 environments, administrators and certain privileged users can access mailbox content through actions such as email preview or message download. While these capabilities are often used for legitimate purposes — such as security investigations, eDiscovery, or incident response — they also represent a potential insider threat or privacy violation risk if misused. Unauthorized access to mailbox data can expose confidential communications, sensitive attachments, or personally identifiable information (PII). Therefore, it’s crucial to continuously monitor when administrators perform actions like: GetMailPreviewUrl – viewing an email’s content through a preview link DownloadEMail – exporting or downloading a full email message If these actions are not tied to a legitimate investigation or security workflow, they could indicate abuse of administrative privileges or data exfiltration attempts.
Microsoft Sentinel (KQL)
