Detects inbound emails from no-reply@filemail.com where the email body's first line is classified with high confidence as a callback scam by an NLP classifier. The rule extracts the first line via regex, runs it through an NLU classifier, and flags messages whose intents include a 'callback_scam' with high confidence. This technique leverages a legitimate file-sharing service to deliver social engineering messages that prompt recipients to call a phone number, often impersonating tech support or financial institutions. The rule combines inbound sender verification with content analysis to identify potential callback phishing, enabling timely detection and investigation of this abuse pattern.