Malicious PDF — malware analysis report

Static analysis result for SHA-256 668884c1bc8b96f2…

MALICIOUS

PDF

153.2 KB Created: 2006-01-04 10:27:41 +01:00 Authoring application: PScript5.dll Version 5.2 (via Acrobat Distiller 5.0 (Windows)) First seen: 2012-11-24
MD5: 7c9f4bb9a686c51bf606cedf44642841 SHA-1: 3581a0d5e48317bc98b01bb05b7b99097ea48945 SHA-256: 668884c1bc8b96f22bf8b1f0c75b5dfef2dba6e1517e2c5a80cdcc409f86efa1
476 Risk Score

Malware Insights

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

The PDF contains JavaScript that utilizes the `exportDataObject` function, which is known to be used for launching embedded executables. Critical heuristics indicate the presence of an embedded PE payload and a launch action targeting cmd.exe, exploiting CVE-2010-1240. The embedded artifact is declared as a PDF but identified as a Windows executable, further confirming the malicious intent to deliver a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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\\Robinsonliste.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://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://purl.org/dc/elements/1.1/In PDF document text
    • https://www.verisign.com/repository/CPS��In extracted file (stream_008_off000127d7.bin)
    • https://www.verisign.comIn extracted file (stream_008_off000127d7.bin)
    • https://www.verisign.com/repository/verisignlogo.gif0��In extracted file (stream_008_off000127d7.bin)
    • https://www.verisign.com/CPS0bIn extracted file (stream_008_off000127d7.bin)
    • http://www.microsoft.com/typographyIn extracted file (stream_008_off000127d7.bin)
    • http://www.iec.chIn extracted file (icc_00_off00011c3f.icc)

Extracted artifacts 8

Files carved from inside the sample during analysis.

FilenameKindSourceSize
Robinsonliste.pdf pdf-embedded-file PDF EmbeddedFile object 40 at offset 0x1D6BC 70144 bytes
SHA-256: 8f1e5763839c7f5443ef7ee7c8b11bb423b0eadb4b4f8d9bd2e5b406ceb2a781
Detection
ClamAV: No threats found
Obfuscation or payload: likely
actual_type=PE; declared_or_context_type=PDF; filename=Robinsonliste.pdf; kind=pdf-embedded-file
javascript_obj0041_000.js pdf-javascript-stream PDF /JS object 41 at offset 0x26096 62 bytes
SHA-256: 8b9c2d701c24e749e8a94b8506e6b7f9589a8cc7a0a652d8c6081c01c9ec7a56
Preview script
First 1,000 lines of the extracted script
this.exportDataObject({ cName: "Robinsonliste", nLaunch: 0 });
stream_003_off00001dc3.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1DC3 43036 bytes
SHA-256: 9aa405459fba1124e98d7c35f81023d86f2baf7366d95baaa54c882654272436
stream_008_off000127d7.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x127D7 10268 bytes
SHA-256: a93408e4d619cbc7cd0ff2e3e459d7272478b8c95426442e923d2a187487a6da
icc_00_off00011c3f.icc pdf-icc-profile PDF ICC profile at offset 0x11C3F 3144 bytes
SHA-256: 2b3aa1645779a9e634744faf9b01e9102b0c9b88fd6deced7934df86b949af7e
font_01_sfnt_off00007985.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7985 17976 bytes
SHA-256: 89b99248cfa7dcd2078ca8f9689abbaa55467b80b7ac0356c91b41ed745a1019
font_02_sfnt_off0000a450.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA450 41516 bytes
SHA-256: ba5ab3269b47776ba6298a0ee9f0cfc3dd0a983d0a97aa153bea183053fd03d2
font_03_sfnt_off0000ff57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF57 15744 bytes
SHA-256: 045dab3614b965c1bec2c1c90ca4176573b6f430a98e943d551124b5cc94d8c9