Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a99b25a6f0e0ff9…

MALICIOUS

PDF

63.8 KB Created: 2010-11-13 13:52:29
MD5: 3efe5c089591a3b9978587f83dcb8dca SHA-1: 977804d1d1452f21df6a7641fc9a1e064db95549 SHA-256: 6a99b25a6f0e0ff906ccf990b6bca5f2823198c3637d2685b623e8a82e57bf97
136 Risk Score

Malware Insights

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

The PDF sample contains embedded JavaScript and triggers heuristics related to PDF JavaScript exploits, specifically mentioning XFA forms. This indicates the file is designed to leverage a vulnerability within PDF viewers to execute arbitrary code. The ML classifier strongly flags this PDF as malicious, supporting the conclusion of an exploit attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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/xci/2.6/
    • http://www.xfa.org/schema/xfa-template/2.6/