Malicious PDF — malware analysis report

Static analysis result for SHA-256 10343efea931f766…

MALICIOUS

PDF

64.3 KB Created: 2011-10-28 00:11:02 +09:00 Authoring application: CubePDF (via GPL Ghostscript 9.04; modified using iTextSharp 5.0.6 (c) 1T3XT BVBA) First seen: 2014-03-08
MD5: 9c427fedbc2e52fc24024e89026bace9 SHA-1: 989386e165c4e8507b1e059f9d4da574e1928b44 SHA-256: 10343efea931f7663c437ceda32dd36b637b1274a8abf02345bdb7e8fa19d39f
476 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.003 Windows Command Shell T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript that utilizes the `exportDataObject` function to launch cmd.exe. The embedded executable payload is disguised with a PDF filename, indicating an attempt to trick the user into executing it. The exploit targets CVE-2010-1240, a known vulnerability for command execution via PDF launch actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 12

  • Adobe Reader Launch action command execution critical CVE exact CVE_2010_1240
    PDF uses the Adobe Reader/Acrobat Launch action pattern associated with CVE-2010-1240: cmd.exe is invoked with attacker-controlled parameters, paired with an embedded/exported payload.
  • ClamAV: Pdf.Tool.Agent-1388586 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Tool.Agent-1388586
  • Launch action critical PDF_LAUNCH
    PDF contains a /Launch action whose target is an executable, URL, or UNC path — can start an external application
  • 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.
  • /Launch action target: cmd.exe critical PDF_LAUNCH_COMMAND
    PDF /Launch action specifies an executable target with parameters '/Q /C %HOMEDRIVE%&cd %HOMEPATH%&(if exist "Desktop\\PDF作成サンプルです.pdf" (cd "Desktop"' — references a known-dangerous executable (cmd, PowerShell, etc.).
  • Embedded attachment masquerades: declared document, content is windows-executable critical PDF_EMBEDDED_FILESPEC_CONTENT_MISMATCH
    An /EmbeddedFile attachment's declared filename extension or /Subtype MIME type contradicts the magic bytes of its decompressed content. The attachment is declared as a benign document or image but the bytes are an executable or executable-bearing archive. This is a deliberate deception used to hide droppers in PDF attachments and is a generic indicator of embed-and-drop weaponisation, independent of any specific CVE.
  • /Launch action paired with attachment-dropping JS API high PDF_LAUNCH_PLUS_DROPPER_JS
    PDF combines a /Launch action with a JavaScript API call that writes or opens an attached/external resource — the canonical shape of the CVE-2010-1240 /Launch + exportDataObject family. Benign PDFs do not pair these surfaces; the combination indicates a drop-and-execute chain regardless of the specific JS API knobs or /Launch target.
  • 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 1 related finding 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
  • 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://ocsp.verisign.com0 In extracted file (PDF.pdf)
    • http://ocsp.verisign.com01In extracted file (PDF.pdf)
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://ns.adobe.com/iX/1.0/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://crl.verisign.com/tss-ca.crl0In extracted file (PDF.pdf)
    • http://crl.verisign.com/ThawteTimestampingCA.crl0In extracted file (PDF.pdf)
    • https://www.verisign.com/rpaIn extracted file (PDF.pdf)
    • https://www.verisign.com/cps0*In extracted file (PDF.pdf)
    • https://www.verisign.com/rpa0In extracted file (PDF.pdf)
    • http://logo.verisign.com/vslogo.gif0In extracted file (PDF.pdf)
    • http://crl.verisign.com/pca3.crl0In extracted file (PDF.pdf)
    • http://csc3-2009-2-crl.verisign.com/CSC3-2009-2.crl0DIn extracted file (PDF.pdf)
    • http://csc3-2009-2-aia.verisign.com/CSC3-2009-2.cer0In extracted file (PDF.pdf)

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
PDF.pdf pdf-embedded-file PDF EmbeddedFile object 28 at offset 0x4671 51244 bytes
SHA-256: 0d5eb9db128ec9053f8c42e01d20e011f154dd90e29829626218e0dc96c8027d
Detection
ClamAV: No threats found
Obfuscation or payload: likely
actual_type=PE; declared_or_context_type=PDF; filename=PDF.pdf; kind=pdf-embedded-file Carved artifact entropy is 7.85, consistent with packed or encrypted content.
javascript_obj0029_000.js pdf-javascript-stream PDF /JS object 29 at offset 0xFCD5 76 bytes
SHA-256: 60bfcf9bf9f1fb384f4fb3e2aeefe156c25d06f5f0095c04a84a5fbccda807fc
Preview script
First 1,000 lines of the extracted script
this.exportDataObject({ cName: "PDF作成サンプルです", nLaunch: 0 });
font_00_sfnt_off0000109c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C 7816 bytes
SHA-256: ae8134755b72a9658a1c79bc884aac6b1b8e536336dccdc8ceb014aded786f45