BEC/Fraud: Generic scam attempt to undisclosed recipients

type.inbound

// undisclosed recipients
and any([recipients.to, recipients.bcc, recipients.cc],
        any(., .display_name =~ "Undisclosed recipients")
)

// mismatched sender (from) and Reply-to
and (
  length(headers.reply_to) > 0
  and all(headers.reply_to,
          .email.domain.root_domain != sender.email.domain.root_domain
  )
)

// generic recipient
and any(ml.nlu_classifier(body.current_thread.text).entities,
        .name == "recipient" and regex.icontains(.text, "(sir|madam)")
)

// request made
and any(ml.nlu_classifier(body.current_thread.text).entities,
        .name == "request"
)

// not a bec scam
and all(ml.nlu_classifier(body.current_thread.text).intents, .name != "bec")

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