Malicious PDF — malware analysis report

Static analysis result for SHA-256 415953c239e2db34…

MALICIOUS

PDF

3.4 KB First seen: 2026-05-10
MD5: 0ca2989bc081a1ffb9974b5541a91d75 SHA-1: 0ec801065993852f30a880d82ead657635dc8f09 SHA-256: 415953c239e2db343fc11d7a05ba40a1a3b6fa873547d16866d8695c2a5cc2b8
118 Risk Score

Malware Insights

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

The PDF contains JavaScript, indicated by the PDF_JAVASCRIPT heuristic. The ML classifier strongly flagged this PDF as malicious. Additionally, the PDF_FILTER_HEX rule indicates the use of ASCIIHexDecode with exploit indicators, suggesting an attempt to obfuscate malicious content. The primary attack vector appears to be the execution of embedded JavaScript, likely to download and execute a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 3

  • JavaScript action low 1 related finding PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • PDF JavaScript rebuilds a builtin via replace() to run a char-code array critical PDF_JS_REPLACE_OBFUSCATED_CHARCODE_BUILDER
    Decoded PDF JavaScript resolves a String builtin from a junked literal — e.g. String['eQvoaol3'.replace(/[3oQS5]/g,'')] yielding fromCharCode/eval — and feeds a large numeric char-code array through it to rebuild and execute the next stage. Dynamically reconstructing a builtin name by stripping junk characters has no benign purpose; paired with the char-code payload array it is an unambiguous obfuscated-JavaScript exploit dropper.
  • 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