Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f0d3f84adc6fd38…

MALICIOUS

PDF

3.9 KB
MD5: cf5407c55e6adab8358ffba697b3a905 SHA-1: 0d7523c9abdf2d9a012e3bf10f2367de0f4eafb8 SHA-256: 3f0d3f84adc6fd38f3b1c2ae58ba8baeb63741b98e8857109defa291b7fd6de4
142 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1566.001 Spearphishing Attachment T1027 Obfuscated Files or Information

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Exploit.Agent-36178. The presence of JavaScript actions, embedded JS streams, and the use of filters like ASCIIHexDecode and ASCII85Decode indicate an attempt to obfuscate and execute malicious code. The primary attack vector is likely the exploitation of a PDF vulnerability to deliver a second-stage payload.

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