Callback phishing via calendar invite

type.inbound
and length(attachments) > 0
and all(attachments, .content_type in ("text/calendar", "application/ics"))
and any(attachments,
        // extract the calendar invite description and use NLU against it
        any(file.explode(.),
            any(.scan.ics.calendars,
                any(.components,
                    any(ml.nlu_classifier(.description).intents,
                        .name == "callback_scam"
                    )
                )
            )
        )
)
and (
  not profile.by_sender_email().solicited
  and not profile.by_sender_email().any_messages_benign
)

// negate highly trusted sender domains unless they fail DMARC authentication
and (
  (
    sender.email.domain.root_domain in $high_trust_sender_root_domains
    and not headers.auth_summary.dmarc.pass
  )
  or sender.email.domain.root_domain not in $high_trust_sender_root_domains
)