• Sublime Core Feed
Medium Severity

Attachment: PDF contains W9 or invoice YARA signatures

Labels

BEC/Fraud
Credential Phishing
PDF
Social engineering
File analysis
YARA

Description

PDF attachment contains YARA signatures commonly associated with fraudulent W9 tax forms or invoice documents, which are frequently used in social engineering attacks to steal sensitive information or facilitate business email compromise.

References

No references.

Sublime Security
Created Feb 4th, 2026 • Last updated Mar 18th, 2026
Feed Source
Sublime Core Feed
Source
GitHub
type.inbound
and any(filter(attachments, .file_type == "pdf"),
        any(file.explode(.),
            any(.scan.yara.matches,
                .name in ("w9_pdf_01", "invoice_pdf_01", "w9_pdf_IDs")
            )
        )
)
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