Sublime Security medium experimental mql

Link: Tax document lure Portuguese/Spanish with suspicious domains

Detects messages in Portuguese/Spanish containing tax document phrases that link to suspicious domains including URL shorteners, free file hosts, or newly registered domains.

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Detection Logic

type.inbound
and 0 < length(body.links) < 15
and length(recipients.to) == 1
and recipients.to[0].email.domain.valid
and (
  // portuguese tax document phrases
  regex.icontains(body.current_thread.text,
                  '(?:documento fiscal
| documento tributário
| documento de imposto
| documento de impostos
| formulário fiscal
| declaração de imposto
| declaração de impostos
| declaração fiscal
| documentação fiscal
| comprovante fiscal
| certidão fiscal
| certificado fiscal
| registro fiscal
| comprovativo fiscal)'
  )
  // spanish tax document phrases
  or regex.icontains(body.current_thread.text,
                     '(?:Acessar Documento
| Documento Fiscal
| documento tributario
| documento de impuestos
| comprobante fiscal
| constancia fiscal
| declaración de impuestos
| formulario fiscal
| documentación fiscal
| registro fiscal
| certificado fiscal)'
  )
)

// suspicious domains
and any(body.links,
        .parser == 'hyperlink'
        and (
          .href_url.domain.domain in $url_shorteners
          or .href_url.domain.root_domain in $url_shorteners
          or .href_url.domain.domain in $free_file_hosts
          or .href_url.domain.root_domain in $free_file_hosts
          or .href_url.domain.domain in $free_subdomain_hosts
          or .href_url.domain.root_domain in $free_subdomain_hosts
          or .href_url.domain.domain in $self_service_creation_platform_domains
          or .href_url.domain.root_domain in $self_service_creation_platform_domains
          or network.whois(.href_url.domain).days_old < 30
        )
        and not .href_url.domain.root_domain in ('sharepoint.com', 'box.com')
)
// subject fields
and regex.icontains(subject.base, '(?:nf
| \b[0-9]{7,10}\b
| nota fiscal)')

// 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)
)

Field Validations

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