Malicious PDF — malware analysis report

Static analysis result for SHA-256 8381060466ea04ca…

MALICIOUS

PDF

3.9 KB
MD5: e209d01238b075d8beb4e66fa802b321 SHA-1: 78e732f761ed95464cd7e1c77255a801c4037715 SHA-256: 8381060466ea04ca585ff9c5947018f2d6ff08b427257cec9707517b3cefadc6
142 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1566.002 Spearphishing Attachment

The file is a PDF identified by ClamAV as 'Pdf.Exploit.Agent-36178' and flagged by a machine learning classifier with high confidence. Multiple PDF-specific heuristics indicate the presence of obfuscated JavaScript streams and decoding filters (ASCIIHexDecode, ASCII85Decode) commonly used in exploit delivery. While no document body text was available for analysis, the combination of these indicators strongly suggests the PDF contains an exploit targeting a PDF reader vulnerability, intended to download and execute a secondary payload.

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