Malicious PDF — malware analysis report

Static analysis result for SHA-256 865fada0033c6c5f…

MALICIOUS

PDF

3.4 KB
MD5: 402d1bab1374d2391348fb6f1b60880d SHA-1: 873731f8d037ee66ea43d1f8f5c9a16beb3ba194 SHA-256: 865fada0033c6c5fc86d30eea95b828dc729a2ee752fa591155307c2153bba56
134 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: Malicious File

The PDF contains embedded JavaScript and uses decoding filters (ASCIIHexDecode, ASCII85Decode) often associated with exploit delivery. A machine learning classifier strongly flagged this PDF as malicious, correlating with the JavaScript signals. The primary attack vector appears to be leveraging JavaScript to execute malicious code within the context of the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 5

  • Correlated malicious PDF JavaScript signals critical PDF_CORRELATED_MALICIOUS_JS
    PDF JavaScript or auto-action content is corroborated by exploit staging, ML, or suspicious extracted-artifact findings. This correlation promotes old exploit-kit PDFs that otherwise remain in the suspicious band because each individual signal is intentionally weighted conservatively.
  • 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