Malicious PDF — malware analysis report

Static analysis result for SHA-256 047186c856aa22b1…

MALICIOUS

PDF

104.0 KB
MD5: f7eccd73ce182ad5f7dc9c283a66367b SHA-1: 18ba21dcea0349ae93f13247d5edef5079b08600 SHA-256: 047186c856aa22b1b90c57900c61cfc90f68a10968e08c7616b06b3cb7ac81c6
268 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF file contains XFA (XML Forms Architecture) which is known to be vulnerable to heap spray attacks. The embedded JavaScript is obfuscated but appears to be constructing a string and likely executing it. This activity, combined with the ML classifier and ClamAV detections, strongly suggests the PDF is designed to exploit this vulnerability to download and execute a malicious payload. The benign URLs present are likely decoys or standard XFA references.

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
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • 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_pdf_script_0000023d.bin
4a701436f175dcec8d6c30adab2b95e840554bad5c8ea92b2b2d3849864265b0
pdf-embedded-script PDF raw stream script payload at offset 0x23D 105777 bytes
Detection
ClamAV: Pdf.Exploit.Agent-36370
Obfuscation or payload: unlikely