Malicious PDF — malware analysis report

Static analysis result for SHA-256 167a4a6bab5c9da3…

MALICIOUS

PDF

12.7 KB
MD5: d4afc532d9b6a74e72ab8f449b1fa8d6 SHA-1: 7c9916d03054bd9b1a5f2ca98e32e8fb186736f4 SHA-256: 167a4a6bab5c9da3799dace76ba988c46ce149e3fcc6ceaab3bfac00926cc944
216 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains XFA forms with embedded JavaScript, triggering a heap spray exploit. This is designed to execute arbitrary code, likely to download and run a second-stage payload. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • XFA form contains risky executable script high CVE related PDF_XFA_SCRIPT
    PDF embeds an XFA form whose script block contains exploit, submission/launch, or shell-execution primitives. Ordinary LiveCycle print/update scripts are left as generic XFA/JS signals unless stronger behavior is present.
  • XFA JavaScript heap-spray exploit code critical PDF_XFA_HEAP_SPRAY
    PDF contains XFA script content with heap-spray or shellcode-like JavaScript markers such as large encoded word sequences, util.pack, large arrays, or spray variable names. This is a weaponised Adobe Reader exploit pattern, not a normal interactive form.
  • ClamAV: Pdf.Exploit.Agent-6136306-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-6136306-0
  • 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
b3dfb90578f89b7900e54b6fd7909d69e8ed2f91865772ab7627b04cba61c34a
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xC8 12261 bytes