Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a60c5caeba1657f…

MALICIOUS

PDF

230.1 KB Created: 2017-08-03 05:27:59 -06:00 Authoring application: Draw (via LibreOffice 5.0)
MD5: 46c863f7812d13aa0685c7227b9c265f SHA-1: d28564ab2455184b28b1aee15b6dff7e1d9a166c SHA-256: 9a60c5caeba1657f67aa67d7c47026ab99434d74a4568464a12b151980341d26
564 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.003 Windows Command Shell T1105 Ingress Tool Transfer T1204.001 User Execution: Malicious Link

This PDF file contains embedded JavaScript and a launch action that executes cmd.exe. The command-line execution is designed to drop and execute an embedded Windows PE payload, identified by ClamAV as Win.Trojan.MSShellcode-7. The PDF itself is also detected as Pdf.Tool.Agent-1388586. The embedded executable is masquerading as a PDF file named 'Temario.pdf'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 14

  • 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.
  • 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\\Temario.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.
  • ClamAV: Pdf.Tool.Agent-1388586 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Tool.Agent-1388586
  • 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 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.
  • Clickable PDF combines external action with parser-evasion structure high PDF_ACTION_PARSER_EVASION
    PDF has an external clickable URI together with object graph or xref structures that make parsers disagree, such as divergent duplicate objects, parser divergence, or xref offset mismatch. That combination is stronger than a plain link: the document is both an outward-action carrier and a parser-confusion/evasion sample.
  • 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
  • External URI low PDF_URI
    PDF contains an external URL action
  • 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.

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
Temario.pdf
770fea5a6f697220a4c877d62e7372b0bb9e84ada954a6fbf5481797bf2ab56f
pdf-embedded-file PDF EmbeddedFile object 72 at offset 0x2E7B7 73802 bytes
Detection
ClamAV: Win.Trojan.MSShellcode-7
Obfuscation or payload: unlikely
javascript_obj0073_000.js
93bd49586c2d9617b66a148b0b1234b4ea268603419b581ee29c4b6f808146e0
pdf-javascript-stream PDF /JS object 73 at offset 0x393F8 56 bytes
font_00_sfnt_off00014080.bin
68ed5ef8696521616f2fe977ab14b7477867383d25c47ebbcab3407180a0a707
pdf-font-stream PDF embedded font (sfnt) at offset 0x14080 11224 bytes
font_01_sfnt_off00015c8c.bin
eb08760642bf3b4df743774a24b9c8e8a1404f4cd119921a96060e6277ad8f2e
pdf-font-stream PDF embedded font (sfnt) at offset 0x15C8C 21588 bytes
font_02_sfnt_off00019805.bin
c12bd58d35f456e5676add1db6b289d108f7c50a2b8fdf9b4e0adca475affd00
pdf-font-stream PDF embedded font (sfnt) at offset 0x19805 3716 bytes
font_03_sfnt_off0001a400.bin
e5cf08d9464cf7a1906b937d6ddf132e16beebe6da7d206b21c543670c98a08b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A400 6480 bytes
font_04_type1_off0001b6b6.bin
33a50f09ed2a533eaef6a34ec17c50c6993cd79a19d77c3bcfcc56cdce2b17e8
pdf-font-stream PDF embedded font (type1) at offset 0x1B6B6 72380 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.99, consistent with packed or encrypted content.