Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b921b38f53b304…

MALICIOUS

PDF

19.1 KB
MD5: 4a7f9d846afbcf705338e58266918014 SHA-1: d372d124f9e382f3bd0facb38034c13e1291d580 SHA-256: 77b921b38f53b30473daf8f12e447e3b41458cc423c6b87debdb472a99facc26
116 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV with the signature Pdf.Exploit.Dropped-78, and a machine learning classifier also flagged it with high confidence. The presence of XFA forms and embedded script payloads indicates an attempt to execute code within the PDF viewer, likely to download and execute a second-stage payload.

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 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 script payload in PDF stream low 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 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
1b663c41e069d95eb407639a5131618b159ed8bbc574cfff9e47f9a9be2027af
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xC8 18771 bytes