Malicious PDF — malware analysis report

Static analysis result for SHA-256 1657908176275239…

MALICIOUS

PDF

33.4 KB
MD5: 4a57674b28ee06646fd1125e951e19fc SHA-1: 2acb6937d8bdc2b61387b0fc1303fabc2502980f SHA-256: 1657908176275239e74d98645f84392b1ed8420dcde20e5933f50585a3e43ec1
74 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file contains embedded JavaScript and uses ASCIIHexDecode and ASCII85Decode filters, indicating an attempt to obfuscate malicious code. The ML classifier strongly flags this PDF as malicious, suggesting it exploits a vulnerability to execute the embedded JavaScript, likely to download and run a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • ASCII85Decode filter (with exploit indicators) low PDF_FILTER_85
    ASCII85 encoding filter present alongside exploit delivery indicators — uncommon outside of obfuscation