Medium Severity

Attachment: PDF with secure document acknowledgment prompt

Description

Detects PDF attachments matching yara rules looking for fake secure document prompts, including acknowledgment-style lures and suspicious image sizing.

References

No references.

Sublime Security
Created Jul 17th, 2026 • Last updated Jul 17th, 2026
Source
type.inbound
and any(filter(attachments, .file_type == "pdf"),
        any(file.explode(.),
            any(.scan.yara.matches,
                .name in (
                  "pdf_prompt_ack_secure_document_link",
                  "pdf_prompt_ack_secure_document_image_sizes"
                )
            )
        )
)
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