Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc2695f88aafc8f3…

MALICIOUS

PDF

141.1 KB Created: 2010-06-29 10:30:35 +08:00
MD5: 32dba580d59fbac648bf378cbb0cd4d9 SHA-1: a84e033ba800bfa96a997ecdde2f3f3ae6e43f72 SHA-256: bc2695f88aafc8f3d7288cb0821a15da7817f78fe4704ab7aac4c5d6b1d06f8b
346 Risk Score

Malware Insights

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

The PDF contains a JavaScript stream that exploits CVE-2009-4324 via the media.newPlayer API. This exploit is designed to download and execute a secondary payload, identified as a Windows executable by ClamAV with the signature Win.Trojan.Agent-756112. The presence of an embedded PE file and the exploit trigger strongly indicate a malicious delivery mechanism.

Heuristics 12

  • 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)
  • Embedded Windows executable payload in PDF stream critical PDF_EMBEDDED_PE_PAYLOAD
    PDF stream bytes contain an embedded Windows executable with a verified PE header. Exploit chains often hide droppers inside ordinary streams rather than standard /EmbeddedFile attachments.
  • 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.
  • 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)
  • Secondary embedded PDF body has suspicious static findings high 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.
  • 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
4bf78f79a1c378d48a8b2977ee5413e21bc602799814d3232f24fc0c954ca4df
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).
embedded_pdf_0001263f.exe
269a7ba964b7fc1dad4198163c0f25f86f974b11cc9a8167582e757cd168c179
embedded-pe PDF decompressed stream PE payload at offset 0x1263F 69101 bytes
Detection
ClamAV: Win.Trojan.Agent-756112
Obfuscation or payload: unlikely
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_off00021c47.pdf
0b1c923c8a0028794f3a3244dc498786746334f394e41678cc58ffbeb707d0a8
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x21C47 6125 bytes