Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6404da85dc36f28…

MALICIOUS

PDF

3.9 KB
MD5: 8c4e10879dcc0dbff14dcbb14e022dec SHA-1: f7f21eaaa08d3c7e90f11b3457aa54b61c6e8249 SHA-256: b6404da85dc36f282fd2748022495e28ec4ba94948f1e48a99e898c04a61981a
112 Risk Score

Malware Insights

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

The critical ClamAV detection indicates this PDF contains an exploit. Heuristics confirm the presence of embedded JavaScript, string decoding functions like String.fromCharCode, and filters (ASCIIHexDecode, ASCII85Decode) often used to obfuscate malicious code within PDFs. The lack of readable document body text and the nature of the heuristics suggest the primary function is exploit delivery.

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