Payroll Pirate: Graph API Mailbox Search for Payroll/HR Keywords Post-AiTM
This rule detects suspicious activity within Microsoft Graph API where an account is querying mailbox contents for sensitive payroll and HR-related keywords. This pattern is often observed following an Adversary-in-the-Middle (AiTM) session compromise, where threat actors (such as those associated with the Payroll Pirate campaign) leverage stolen session tokens to exfiltrate sensitive employee information by searching for specific financial and payroll keywords across multiple mailboxes.
Microsoft Sentinel (KQL)

