Malicious PDF — malware analysis report

Static analysis result for SHA-256 50d2649a9b345c9a…

MALICIOUS

PDF

3.9 KB
MD5: 03e81493b2bdc7677c6423450da05736 SHA-1: fd1cfe9759ce08f08634c7da7752832c6591edc3 SHA-256: 50d2649a9b345c9a3cb3a00f1f971e7e792bf183848250e4daf9360dac19151e
142 Risk Score

Malware Insights

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

The file is a PDF containing embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT and PDF_JS. The presence of ASCIIHexDecode and ASCII85Decode filters, along with a high ML score and ClamAV detection (Pdf.Exploit.Agent-36178), strongly suggests it exploits a known PDF vulnerability. The embedded JavaScript is likely responsible for downloading and executing a secondary payload, a common technique for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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