Malicious PDF — malware analysis report

Static analysis result for SHA-256 340b4dc0ef383d78…

MALICIOUS

PDF

291.6 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: 74be75998f5c349b855df66acc744506 SHA-1: 2c393a5d9077bacc39c644c21c3b4bdb7554e3af SHA-256: 340b4dc0ef383d7865ca373fdda5913eced914817fd043626bea90dc462c8332
448 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript T1566.001 Spearphishing Attachment

This PDF document exploits CVE-2007-5659 via embedded JavaScript, as indicated by multiple critical heuristic firings including PDF_JS_EXPLOIT_CLUSTER and CVE_2007_5659. The embedded JavaScript, specifically the unescaped string, likely decodes and executes a second-stage payload. ClamAV detection of 'Pdf.Exploit.Agent-35908' further confirms its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 14

  • 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-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
  • 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.
  • 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 6

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
font_01_sfnt_off00027e35.bin
034125c791462832bef7f0b0ea73b8d67c0d43016431e901a81a01a85e980150
pdf-font-stream PDF embedded font (sfnt) at offset 0x27E35 21928 bytes
font_02_sfnt_off0002adfc.bin
25c62999f96b13a21d56b0349a186ac43ae8735716ca006ffcff0f052008f24a
pdf-font-stream PDF embedded font (sfnt) at offset 0x2ADFC 301520 bytes
polyglot_child_pdf_off00026585.pdf
799dc1614826637410f334da0575e71ef68cbd0dcd8a1780168efe8fd15a95eb
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x26585 141578 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35908
Obfuscation or payload: unlikely
polyglot_child_pdf_off0003bb35.pdf
ef49a2e6fb779c4ec58b062dd3977a587b05d5572b66d0d3663c801f5fc91623
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x3BB35 54106 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35908
Obfuscation or payload: unlikely