Malicious PDF — malware analysis report

Static analysis result for SHA-256 b174b8870159d724…

MALICIOUS

PDF

11.7 KB
MD5: a4cda28f6eb20e2008d55f600ec5c556 SHA-1: 70af7e5774dc06597afa3cfc7e78ead65655c8a7 SHA-256: b174b8870159d7247e4d761602322f07c932ad8c4eeed8f4f5b8d2b80ee5a6f0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1566.002 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as Pdf.Exploit.Dropped-78. Heuristics indicate the presence of an embedded script payload and an embedded file, suggesting it is designed to drop and execute a secondary malicious component. The embedded URLs, while not directly malicious, are associated with XFA forms, a common vector for PDF exploits.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • ClamAV: Pdf.Exploit.Dropped-78 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Dropped-78
  • Embedded script payload in PDF stream medium PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xfa-template/2.5/
    • http://www.xfa.org/schema/xfa-data/1.0/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0008.bin
12d635d5afd467155dad03ed88c4d6ff2c2309c9c84c131f5377c3fe1e58abc8
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xC8 11257 bytes