Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7ea78e87322261a…

MALICIOUS

PDF

8.0 KB First seen: 2026-05-11
MD5: 98b4a03435b84558521ed2f909ff7ee1 SHA-1: 0886ca6ef86f91521dfa8193044d4ca77e84708c SHA-256: b7ea78e87322261a69960767b918a1b503cff62de7663e78a75ee8919a00c527
118 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and uses ASCIIHexDecode filters, which are common indicators of malicious PDFs. The ML classifier strongly flagged this file as malicious. While no specific exploit or payload is directly visible, the presence of JavaScript suggests an attempt to execute arbitrary code, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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