Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a16b6e8463cc4ef…

MALICIOUS

PDF

3.9 KB
MD5: 7f1c07c38ea98af993b17f8e1dcc878b SHA-1: 8dbbabf9edc12fc2220e14e98ffdee0eeacebcaa SHA-256: 3a16b6e8463cc4ef7ad9e3395076aee4fd02dfd0ea849ff231624e23017f0d25
112 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT and PDF_JS. The presence of PDF_FILTER_HEX and PDF_FILTER_85 filters, along with ClamAV detecting it as Pdf.Exploit.Agent-36178, strongly suggests exploitation of a PDF vulnerability. The embedded JavaScript is likely used to download and execute a secondary payload, although the exact functionality cannot be determined due to the lack of readable document body text and script content.

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