Malicious PDF — malware analysis report

Static analysis result for SHA-256 d919caa3e109db68…

MALICIOUS

PDF

3.8 KB
MD5: 14cf88883e0230149efaa3e9508155d6 SHA-1: 6bcf65bf9835b7976dd8b9464bd8d23382c382fb SHA-256: d919caa3e109db688420f82b159fdaaa9392fd330d76e32d6e521643e1b936a9
142 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically detecting an exploit. Heuristics indicate the presence of JavaScript and the use of PDF filters like ASCIIHexDecode and ASCII85Decode, which are often employed to obfuscate malicious code within PDF documents. The ML classifier's high confidence score and the ClamAV detection strongly suggest this PDF contains an exploit, likely leading to arbitrary code execution.

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