Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4bae674989cf0d9…

MALICIOUS

PDF

9.6 KB Created: 2008-04-28 12:17:40 +03:00
MD5: 024918da3be2884fd38258541a4b4e68 SHA-1: e4413795d1e42a3ca39bd1563b4f6207c7f496ac SHA-256: d4bae674989cf0d9372f0683c5eb231a7b1e8f06fbc303fe70c630fa56b26b5d
104 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, and PDF_EVAL. The ML classifier strongly flagged this PDF as malicious. The embedded JavaScript stream, named javascript_obj0016_000.js, is likely responsible for executing the malicious payload. While the exact nature of the payload is not fully discernible from the provided evidence, the presence of eval() and String.fromCharCode suggests obfuscation and dynamic code execution, typical of PDF-based malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 7

  • 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.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/iX/1.0/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0016_000.js
ae311e2020d81bfbac1df247e9a0324616874c6da2ac8a495c7fe7000fb6c913
pdf-javascript-stream PDF /JS object 16 at offset 0x931 7382 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 6 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).