Detect Credential Harvesting Pages in Email

This rule detects potential credential harvesting attempts by identifying emails that contain keywords commonly associated with phishing (e.g., 'password', 'update', 'verify' in the subject) and URLs that suggest login or account pages (e.g., 'form', 'login', 'account'). It aggregates these events from the same sender over a one-hour period and flags senders with three or more such emails.