sublimemediumRule

Attachment: PDF with embedded box-lure and javascript

Detects inbound messages containing a PDF attachment that matches YARA signatures looking for JavaScript functions or specific lure boxes that have been observed within malicious documents.

MITRE ATT&CK

T1566 T1566.001 T1566.002 T1598 T1204.002 T1486 T1036 T1027

initial-accessdefense-evasion

Detection Query

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

Data Sources

Email MessagesEmail HeadersEmail Attachments

Platforms

Raw Content

name: "Attachment: PDF with embedded box-lure and javascript"
description: "Detects inbound messages containing a PDF attachment that matches YARA signatures looking for JavaScript functions or specific lure boxes that have been observed within malicious documents."
type: "rule"
severity: "medium"
source: |
  type.inbound
  and any(filter(attachments, .file_type == "pdf"),
          any(file.explode(.),
              any(.scan.yara.matches,
                  .name in ("pdf_js_function_box_lure", "pdf_rect_size_box_lure")
              )
          )
  )
attack_types:
  - "Credential Phishing"
  - "Malware/Ransomware"
tactics_and_techniques:
  - "PDF"
  - "Social engineering"
  - "Evasion"
detection_methods:
  - "File analysis"
  - "YARA"
id: "142d9aee-66b0-54e7-82f5-5d0817385ff9"