Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb1503f27482839e…

MALICIOUS

PDF

84.1 KB Created: 2010-06-29 10:30:35 +08:00 Authoring application: Acrobat 编辑器 8.0 (via Adobe Acrobat 8.0)
MD5: 6c7c198cc3f180c5f569581138b995b0 SHA-1: 6a4e982e5510e6c00bb9bf3f3a14e8a6382fcfb4 SHA-256: fb1503f27482839e691df390a5c8d3cfdc16c20eb770e9983966c9be11e12732
246 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains embedded JavaScript that leverages the CVE-2009-4324 vulnerability via the media.newPlayer API. This script is designed to download and execute a secondary payload, as indicated by the 'PDF_JAVASCRIPT', 'PDF_JS', and 'CVE_2009_4324' heuristic firings. The presence of an embedded file and a secondary PDF further supports the multi-stage nature of the attack. The document body is heavily obfuscated and does not provide direct clues to the lure.

Heuristics 10

  • 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. (identified after JavaScript deobfuscation)
  • Secondary embedded PDF body has suspicious static findings critical POLYGLOT_CHILD_PDF_STATIC_TRIAGE
    A valid PDF body was found at a nonzero offset inside another container and its carved contents matched PDF exploit or lure heuristics. This catches polyglots where the top-level magic routes to ZIP/OLE while a PDF reader or downstream parser opens the hidden PDF payload.
  • RichMedia (Flash) high PDF_RICHMEDIA
    PDF contains /RichMedia (Adobe Flash) which is a historic exploit vector (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • Suspicious extracted artifact medium EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • 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. (matched inside decoded stream)
  • 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. (matched inside decoded stream)
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload (matched inside decoded stream)
  • PDF paints image(s) but contains no text operators info PDF_IMAGE_ONLY_LURE
    PDF has 1 image XObject(s) and the content stream contains no text-emitting operators (BT/ET, Tj, TJ, ', ") in either raw bytes or decompressed streams — this is the screenshot-as-PDF pattern used to bypass text-based scanners and to deliver instructions purely through rendered pixels. It is informational unless paired with invisible links or risky URI context.
  • 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/xap/1.0/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/pdf/1.3/

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off00000392.bin
1c1c8591e38f42179ce46b38cc8ed5645605282a354ff251f7b2d9182b2a631c
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x392 4264 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 3 long base64-like blob(s). Carved artifact contains 1 long hex-escaped blob(s).
legacy_pdfkit_stage_000.js
42c3f4df375ff6f58ff655cc4f88b5cc28f0dd33b978390db3538684a6219b74
deobfuscated-js string-concatenation normalized Acrobat API aliases at offset 0x392 126 bytes
objstm_0017_00.bin
dd7918c182d6e2b8d996a6b8ee81663c49a0cb297efe1e1fa3c5af0c987bde84
pdf-objstm-decoded PDF /ObjStm 17 0 obj (inflated) 871 bytes
polyglot_child_pdf_off00011e83.pdf
c11e03ac3120cdf0cd05eece897322e896c303597d3fb0ca37da9cb3fa4f3e07
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x11E83 12786 bytes
polyglot_child_pdf_off00013888.pdf
0b1c923c8a0028794f3a3244dc498786746334f394e41678cc58ffbeb707d0a8
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x13888 6125 bytes