Malicious PDF — malware analysis report

Static analysis result for SHA-256 bbf4cf03f230b7f8…

MALICIOUS

PDF

3.9 KB
MD5: 948f2e543c475674b396fadc7c85e002 SHA-1: 767469bd90f37dbd6e575b0a233bb0898b5a00b3 SHA-256: bbf4cf03f230b7f8ad3ed03307a34867c22e61ead6b112836cd1ebfe9450b2ec
112 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/Shell Scripting: JavaScript T1204.002 Malicious File: Malicious JavaScript

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT and PDF_JS. The use of ASCIIHexDecode and ASCII85Decode filters, along with the ClamAV detection of '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 second-stage payload.

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