Malicious PDF — malware analysis report

Static analysis result for SHA-256 498d68797b385f92…

MALICIOUS

PDF

3.4 KB First seen: 2026-05-11
MD5: 965852fb9a0b3f99bd104ad71b01b1da SHA-1: 57221fb3e65a85157b7352dd79ff66d63ee41166 SHA-256: 498d68797b385f920d5da981845614c18cb1e5f77ac0662fea5726f9d9f137bb
118 Risk Score

Malware Insights

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

The PDF contains JavaScript and uses ASCIIHexDecode filters, indicating an attempt to obfuscate malicious content. The ML classifier strongly suggests malicious intent. The presence of JavaScript actions points to an attack pattern involving script execution, likely to exploit a vulnerability or deliver 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