Attachment: PDF with embedded box-lure and javascript

calendar Aug 19, 2026  ·
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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.

Sublime rule (View on GitHub)

 1name: "Attachment: PDF with embedded box-lure and javascript"
 2description: "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."
 3type: "rule"
 4severity: "medium"
 5source: |
 6  type.inbound
 7  and any(filter(attachments, .file_type == "pdf"),
 8          any(file.explode(.),
 9              any(.scan.yara.matches,
10                  .name in ("pdf_js_function_box_lure", "pdf_rect_size_box_lure")
11              )
12          )
13  )  
14attack_types:
15  - "Credential Phishing"
16  - "Malware/Ransomware"
17tactics_and_techniques:
18  - "PDF"
19  - "Social engineering"
20  - "Evasion"
21detection_methods:
22  - "File analysis"
23  - "YARA"
24id: "142d9aee-66b0-54e7-82f5-5d0817385ff9"
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