Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb726892830df9cb…

MALICIOUS

PDF

3.9 KB
MD5: fbadeb29cadc2b35d083e6c19314bfa8 SHA-1: 46577961fb6545d370e6769af82ad270953db33e SHA-256: fb726892830df9cbb0f588cbe159c6acb291c873e656b7e2ba60d3d954fdac76
142 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT and PDF_JS. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically identifying it as Pdf.Exploit.Agent-36178. The presence of ASCIIHexDecode and ASCII85Decode filters, often used for obfuscation in exploits, further supports this. The embedded JavaScript is likely responsible for exploiting a vulnerability within the PDF reader to achieve its malicious objective.

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