Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf2b7d6958f5c9b3…

MALICIOUS

PDF

3.9 KB
MD5: 3a4680d9aae6d7b21931197a078917c6 SHA-1: 89488bb1046bcf227d6e2d122c4fca0d1988d535 SHA-256: bf2b7d6958f5c9b3169d7fc8ffbe805f48a71d8b16e2ce88dcac1193e0d3b87b
112 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript T1204.002 Malicious JavaScript

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT and PDF_JS. The presence of ASCIIHexDecode and ASCII85Decode filters, along with ClamAV detection as Pdf.Exploit.Agent-36178, strongly suggests this is a malicious PDF exploiting a vulnerability. The embedded JavaScript is likely responsible for downloading and executing a secondary payload, a common technique for initial access.

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