Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a37996166dd66d5…

MALICIOUS

PDF

27.3 KB
MD5: 96227a5e83088f9c9e5de62ca7ecb4cc SHA-1: 46aa6ea803bbe38cbb80016f407f7c845c190dde SHA-256: 2a37996166dd66d5c694651cd6b8b281dded18a8f38c158de1cd1e44d7c047e4
134 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File

The PDF contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, and PDF_CORRELATED_MALICIOUS_JS. The ML classifier also strongly flagged this PDF as malicious. The presence of ASCIIHexDecode and ASCII85Decode filters, often used for obfuscation in malicious PDFs, further supports this assessment. The primary attack vector appears to be the execution of malicious JavaScript embedded within the PDF document.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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