Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfe647765ce647d5…

MALICIOUS

PDF

1.6 KB
MD5: dbf26526225d99832eb848a94d3b75b9 SHA-1: b9e553ce37e281733448c9ce6de06d0a29bf18bb SHA-256: dfe647765ce647d52eb4504e94df494c7e4cf09f322d4f65521e43eb5c82c82e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 Command and Scripting Interpreter: PowerShell T1059.003 Command and Scripting Interpreter: Windows Command Shell T1059.007 Command and Scripting Interpreter: JavaScript/TypeScript

The PDF file contains obfuscated JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, PDF_EVAL, and PDF_FROMCHARCODE. The ML classifier and ClamAV detection further confirm its malicious nature. The embedded JavaScript file, javascript_obj0009_000.js, is likely responsible for executing the malicious payload, although its specific actions are obscured by obfuscation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Heuristics.PDF.ObfuscatedNameObject critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Heuristics.PDF.ObfuscatedNameObject
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0009_000.js
e4f6d89af92093d63774611d5f50ff3a4de7e7afa5bf40394df1c68cc34bd006
pdf-javascript-stream PDF /JS object 9 at offset 0xDC 3898 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).