Malicious PDF — malware analysis report

Static analysis result for SHA-256 23d485643d3ad0ab…

MALICIOUS

PDF

35.1 KB Created: 2009-08-30 00:20:17 UTC Authoring application: AdobePS5.dll Version 5.2.2 (via Mac OS X 10.5.8 Quartz PDFContext)
MD5: c4080034e8701057cd44c6757110a29d SHA-1: 4c91439be100045d9338b6fed33c1e0d49c6a216 SHA-256: 23d485643d3ad0ab33757249f2150335600db0ea25ed3f4bc227ac32c8f073f2
484 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.003 Windows Command Shell T1105 Ingress Tool Transfer

The PDF file contains embedded JavaScript that triggers a launch action, exploiting CVE-2010-1240 to execute cmd.exe. This action is designed to drop and execute an embedded Windows executable payload, which is disguised as 'form.pdf'. The embedded artifact was detected by ClamAV as Win.Trojan.ShellcodeReverseTcp-1, indicating a malicious downloader or trojan.

Heuristics 11

  • 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\\form.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.
  • 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
form.pdf
df4f452e51b48076c37591cbae881ee644fa7bd5b7ed5e958dd35b1ac3827895
pdf-embedded-file PDF EmbeddedFile object 21 at offset 0x3B9E 37888 bytes
Detection
ClamAV: Win.Trojan.ShellcodeReverseTcp-1
Obfuscation or payload: unlikely
javascript_obj0022_000.js
eff4a0943aaff2d99cb5c8666337775c91d4d5f687782df94d2c5fc77becde7f
pdf-javascript-stream PDF /JS object 22 at offset 0x8872 53 bytes
icc_00_off000002d6.icc
2b3aa1645779a9e634744faf9b01e9102b0c9b88fd6deced7934df86b949af7e
pdf-icc-profile PDF ICC profile at offset 0x2D6 3144 bytes