Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d1b93e5ffe804ba…

MALICIOUS

PDF

18.8 KB
MD5: bccdad7b52701cd2e5883c7b34319413 SHA-1: 7c2b087884aad320c89d2158fdb4b309da23376f SHA-256: 8d1b93e5ffe804ba3fc15bb23ffbca56e65b6e51d7be829402a484a343db863f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution: Malicious File T1566.002 Phishing: Spearphishing Attachment

The file is identified as malicious by multiple high-confidence heuristics, including ML classification and ClamAV detection (Pdf.Exploit.Dropped-78). The presence of an embedded script payload and an embedded file strongly suggests it's designed to exploit a vulnerability within the PDF reader to download and execute a secondary payload. The XFA form structure also indicates a potential attack vector.

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
9c758dce9b98c6b292b79a1c00882c836e62332d19f9d577352538baf9558bf1
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xC8 18540 bytes