Malicious PDF — malware analysis report

Static analysis result for SHA-256 016d627912376ab0…

MALICIOUS

PDF

96.3 KB Created: 2008-03-23 21:04:24 +08:00 Authoring application: Acrobat PDFMaker 6.0 for Word (via Acrobat Distiller 6.0 (Windows))
MD5: eec66d0fe9dc95e44766616ebeda8797 SHA-1: 099f6d6da35525cf6cfd106400113f139a3ef0b0 SHA-256: 016d627912376ab01db9d2d3932b7e320a157f37c4e4da0dda2ab62a3960fc81
394 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes the unescape() function and targets CVE-2007-5659 (Collab.collectEmailInfo). This JavaScript is designed to execute a malicious payload, as indicated by the 'PDF_JS_EXPLOIT_CLUSTER' and 'ML_NYX_PDF_MALICIOUS' heuristics. The embedded artifact 'javascript_obj0026_000.js' and the secondary embedded PDF 'polyglot_child_pdf_off00015f0f.pdf' are also suspicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 12

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (matched in decompressed stream)
  • 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.
  • 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.
  • ClamAV: Pdf.Exploit.Agent-35910 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35910
  • 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.
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PSSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • Suspicious extracted artifact info 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.
  • 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/iX/1.0/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/pdfx/1.3/
    • http://ns.adobe.com/photoshop/1.0/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://purl.org/dc/elements/1.1/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0026_000.js
d0df66b11dbf0cd664b6c76a1eef4dab9b57a30dde908f9a13a812cb2f19a6a9
pdf-javascript-stream PDF /JS object 26 at offset 0xA7D 3408 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 17 eval/decoder/string-building token(s).
polyglot_child_pdf_off00015f0f.pdf
48d5bb29400ba6117fcc699589e98e2e9c72a393357b00013fe946463965cc6f
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x15F0F 8703 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35910
Obfuscation or payload: unlikely