Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3fae2d59826c4f1…

MALICIOUS

PDF

319.9 KB Created: 2008-06-04 16:34:23 +08:00 Authoring application: Acrobat PDFMaker 6.0 for Word (via Acrobat Distiller 6.0 (Windows))
MD5: 8b99c883a78a88695af73207a1e35087 SHA-1: 02de21cba34113232798d48f7d0cfbff67cdcc9e SHA-256: e3fae2d59826c4f18770e87b7d2d4284ab8dd0bf84abe7d540f97e53b5d9985f
356 Risk Score

Malware Insights

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

The PDF file contains critical heuristic firings for CVE-2007-5659 (Collab.collectEmailInfo) and a PDF launch action, indicating exploitation of a known vulnerability. It also contains embedded JavaScript and an embedded PDF, suggesting a multi-stage attack. The embedded JavaScript stream was unescaped and contained suspicious content, likely to facilitate the execution of the embedded PDF.

Heuristics 13

  • 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)
  • 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-35908 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35908
  • 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.
  • Launch action high PDF_LAUNCH
    PDF contains a /Launch action with an unresolved or extension-less target — treat as potentially dangerous
  • 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.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • 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/xhtml
    • http://www.xfa.org/schema/xfa-data/1.0/
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0038_000.js
daa30e3bb075b650c7e10ec3bd2a26302bb701ac90ceba112d5c347128f520ca
pdf-javascript-stream PDF /JS object 38 at offset 0x5B3F 3308 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 17 eval/decoder/string-building token(s).
font_00_sfnt_off00000dfc.bin
0ae970ad7c344cf28e606b6203b3502c53eabe1b6a47f5c7433ba997f206f18b
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC 181668 bytes
polyglot_child_pdf_off00042c6f.pdf
28cc0f221ce63d0c9e1fab52d7cc4a05dd8c1e0cb0f1448e1749e296f4d895d3
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x42C6F 54106 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35908
Obfuscation or payload: unlikely