Malicious PDF — malware analysis report

Static analysis result for SHA-256 22a67523749d7128…

MALICIOUS

PDF

3.4 KB First seen: 2026-05-10
MD5: 8241cbe569d8d41409b5fa7d152b6394 SHA-1: 0cfc001788716bf5b089dba2a6b3f71bf9b86578 SHA-256: 22a67523749d7128ab2245ab924a5a83904898d02aa715e6e78760bb95e821c4
118 Risk Score

Malware Insights

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

The PDF contains JavaScript and uses an ASCIIHexDecode filter, indicating an attempt to obfuscate malicious content. The ML classifier strongly suggests malicious intent. The presence of JavaScript points to an attempt to execute arbitrary code, likely to download and run a second-stage 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