Brand impersonation: DocuSign with embedded QR code

name: "Brand impersonation: DocuSign with embedded QR code"
description: "This rule detects unsolicited messages with short bodies containing a DocuSign logo, QR code language and an embedded QR code."
type: "rule"
severity: "high"
source: |
  type.inbound
  and length(body.current_thread.text) < 1000
  and length(attachments) == 0
  and regex.icontains(body.current_thread.text, '\bQ(\.)?R(\.)?\b')
  and regex.icontains(body.current_thread.text, "scan|mobile|camera")
  and any(ml.logo_detect(file.message_screenshot()).brands,
          strings.starts_with(.name, "DocuSign")
  )
  //
  // This rule makes use of a beta feature and is subject to change without notice
  // using the beta feature in custom rules is not suggested until it has been formally released
  //
  and any(beta.scan_qr(file.message_screenshot()).items,
          .type is not null and regex.contains(.data, '\.')
  )
  and (
    not profile.by_sender().solicited
    or (
      profile.by_sender().any_messages_malicious_or_spam
      and not profile.by_sender().any_messages_benign
    )
  )
  and not profile.by_sender().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
  )
attack_types:
  - "Credential Phishing"
tactics_and_techniques:
  - "Evasion"
  - "Image as content"
  - "Impersonation: Brand"
  - "QR code"
detection_methods:
  - "Computer Vision"
  - "Content analysis"
  - "QR code analysis"
  - "Sender analysis"
id: "f5cde463-68ed-5dd5-a806-7a835f0b4d7c"