Malicious PDF — malware analysis report

Static analysis result for SHA-256 823638e1b8617a59…

MALICIOUS

PDF

45.3 KB
MD5: 7f8e8905af77895a422730ae89b94336 SHA-1: c5c133e6da4057ef9d01d62fe0c0e9392d44cd05 SHA-256: 823638e1b8617a5980ee2eaafdc997ac44755724f10a1564b8d6cecd95d1aac4
514 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1566.002 Spearphishing Attachment T1059.003 Windows Command Shell T1105 Ingress Tool Transfer

The PDF file contains embedded JavaScript that utilizes the 'exportDataObject' API, indicating an attempt to drop an attachment. This attachment is identified as a Windows executable by ClamAV. The PDF also contains a launch action targeting 'cmd.exe' with parameters that suggest it attempts to execute the dropped payload. The embedded executable is named 'template.pdf', further attempting to disguise its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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\\template.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.Dropper.Agent-7277697-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7277697-0
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
template.pdf
24bc9554ec6f673c43a23ae2e2d7925862618edb7d49d48bbfc678c0505de0b8
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0x3B5 73802 bytes
Detection
ClamAV: Win.Trojan.MSShellcode-6360728-0
Obfuscation or payload: unlikely
javascript_obj0009_000.js
bc1d5cdfa608238e3cd965aa51949d02f8ab713463ea0beb61ec928b121788d1
pdf-javascript-stream PDF /JS object 9 at offset 0xB02C 57 bytes