Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a663975f2d6e958…

MALICIOUS

PDF

3.8 KB
MD5: f3d3b8e50cdb65ed8c3750ebd4eb7363 SHA-1: ca95337c52d12b8bffdcb40770c1bed1084ae5e0 SHA-256: 3a663975f2d6e9582eaa1cb188a839f04e9ddf9d0f9e81331e74bca69c67f931
142 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically indicating an exploit. Heuristics indicate the presence of JavaScript and the use of ASCIIHexDecode and ASCII85Decode filters, common in PDF exploits. The ML classifier output of 0.999984 strongly suggests malicious intent, likely to execute arbitrary code via embedded JavaScript.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • ClamAV: Pdf.Exploit.Agent-36178 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36178
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • ASCII85Decode filter (with exploit indicators) low PDF_FILTER_85
    ASCII85 encoding filter present alongside exploit delivery indicators — uncommon outside of obfuscation