Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d515110ffc05cfb…

MALICIOUS

PDF

3.4 KB First seen: 2026-05-11
MD5: a667e45d6177346e6ae764c21dc1c359 SHA-1: fde978552857043983110acc005e1a4708c06407 SHA-256: 1d515110ffc05cfb10245505b5ab1feb8ecb533869f8416078cd85552217da0b
118 Risk Score

Malware Insights

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

The ML classifier strongly indicates this PDF is malicious. Static analysis detected JavaScript actions and the use of ASCIIHexDecode filters, which are common in PDF exploits. The combination suggests the PDF is intended to deliver a malicious payload, likely through JavaScript execution.

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