Malicious PDF — malware analysis report

Static analysis result for SHA-256 842623173ada920e…

MALICIOUS

PDF

3.8 KB
MD5: 0b785f7fcbf0baf1bf48b6a9410ee14a SHA-1: 7abd6998cde35acc53994d8fae950f57d7bd2be4 SHA-256: 842623173ada920e91afee7f9cb502c049c8d8e653e7b6313f9719854e1d7ceb
142 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1059 Command and Scripting Interpreter

The file is identified as a malicious PDF by ClamAV and a machine learning classifier. Heuristics indicate the presence of JavaScript and the use of PDF filters like ASCIIHexDecode and ASCII85Decode, often employed in exploit delivery. The ML classifier's high confidence score further supports its malicious nature. The PDF structure suggests an attempt to execute embedded JavaScript, likely to download and run a secondary 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