Malicious PDF — malware analysis report

Static analysis result for SHA-256 33fe5e53acacb26f…

MALICIOUS

PDF

99.0 KB Created: 2009-07-08 10:53:46 +08:00 Authoring application: Acrobat Distiller 7.0 (Windows)
MD5: 9f5e718e4a43c92fb76d050e0b897284 SHA-1: 818926bfcf9e7a81aef805a036e5f93a0bfc58f9 SHA-256: 33fe5e53acacb26f0b2b5ac941947728d0acfa6fe5e4b56d68f7be59d651def8
148 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that exploits CVE-2009-4324, indicated by the 'media.newPlayer' heuristic. The JavaScript is heavily obfuscated but appears to be a downloader for a second-stage payload. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 5

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (matched in decompressed stream)
  • Generic recovered JavaScript exploit stage high PDF_GENERIC_STAGE_RECOVERY
    Bounded static stage recovery exposed hidden JavaScript through generic transforms such as null-byte collapse, percent decoding, marker replacement, arithmetic character codes, fromCharCode, numeric arrays, numeric-array minus-key decoders, alphabet-index arrays, /Producer half-difference metadata arrays, hex literals, marker-stripped Base64 literals, custom 6-bit XOR table decoders, or repeated-marker hex carriers. This rule is emitted only when the recovered stage contains exploit-like Acrobat JavaScript or shellcode markers.
  • 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.
  • 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://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/pdfx/1.3/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0017_000.js
828ebb87163ecaf16d413e543f080da83ca41597d02b835da55542898af11cb3
pdf-javascript-stream PDF /JS object 17 at offset 0x4DA 3089 bytes
generic_stage_recovery_000.js
e6ebe669e360ed7297e6e6bf73739c135dbc14e66c7f3ad6520dba11bc6eec99
deobfuscated-js generic stage recovery split-literal-normalize from JavaScript object 17 at offset 0x4DA 2925 bytes