sublimehighRule

Attachment: PDF with W-9 form indicators

Detects inbound messages containing PDF attachments that match structural or signature patterns consistent with specific W-9 tax lure activity sets.

MITRE ATT&CK

T1566.002 T1534 T1656 T1566 T1598 T1598.003

initial-access

Detection Query

type.inbound
and any(filter(attachments, .file_type == "pdf"),
        any(file.explode(.),
            any(.scan.yara.matches,
                .name in ("w9_c001_signatures", "w9_c001_structure")
            )
        )
)

Data Sources

Email MessagesEmail HeadersEmail Attachments

Platforms

Raw Content

name: "Attachment: PDF with W-9 form indicators"
description: "Detects inbound messages containing PDF attachments that match structural or signature patterns consistent with specific W-9 tax lure activity sets."
type: "rule"
severity: "high"
source: |
  type.inbound
  and any(filter(attachments, .file_type == "pdf"),
          any(file.explode(.),
              any(.scan.yara.matches,
                  .name in ("w9_c001_signatures", "w9_c001_structure")
              )
          )
  )
attack_types:
  - "BEC/Fraud"
tactics_and_techniques:
  - "PDF"
  - "Social engineering"
  - "Impersonation: Brand"
detection_methods:
  - "YARA"
  - "File analysis"
  - "Content analysis"
id: "1ff3445d-539e-57f9-b578-447f34933129"