Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f3c963884ff302e…

MALICIOUS

PDF

3.8 KB
MD5: 67ae97f2f177aa526a7ee6e9652f8bde SHA-1: 28279bac2993b172eb3f1a6240606091f06cee60 SHA-256: 8f3c963884ff302ee6b490a374842f1bef05fb34284fbdab23bb11b3dcedbf11
112 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1566.002 Spearphishing Attachment

The PDF contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT and PDF_JS. The use of ASCIIHexDecode and ASCII85Decode filters, along with the critical ClamAV detection of 'Pdf.Exploit.Agent-36178', strongly suggests this PDF is designed to exploit a vulnerability and execute malicious code. The exact nature of the exploit and payload is not discernible from the provided evidence, but the intent is clearly malicious exploitation.

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