Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a1915bcd5c4c682…

MALICIOUS

PDF

3.4 KB First seen: 2026-05-10
MD5: 3de20779c68919bdf5333171308a34e6 SHA-1: 93c7dee0c2c51283c0d69d4f2ed7cd19368234d8 SHA-256: 1a1915bcd5c4c6826ac31f689245d2e5fe31b2ed0d2852064d39e9d8e8c6e50f
118 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, indicated by the PDF_JAVASCRIPT heuristic. Additionally, the PDF_FILTER_HEX rule fired with exploit indicators, suggesting obfuscation and potential exploitation. The ML classifier strongly flags this PDF as malicious. The combination of these factors points to a malicious PDF designed to execute embedded scripts.

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