Malicious PDF — malware analysis report

Static analysis result for SHA-256 934c8c98cb919963…

MALICIOUS

PDF

3.4 KB First seen: 2026-05-10
MD5: 0c03b13a75b3fe667a5bf24526368943 SHA-1: 87cc2c087fb070560eceb8f3f949afb219d57481 SHA-256: 934c8c98cb919963d5de8b28e8572fe45da9509b33d072d8685d00e063a4d276
118 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and uses ASCIIHexDecode filters, indicating an attempt to obfuscate malicious content. The ML classifier strongly suggests malicious intent. The combination of these factors points to a likely exploit delivery mechanism within the PDF, designed to execute further malicious code.

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