Malicious PDF — malware analysis report

Static analysis result for SHA-256 03bdca2cef60f144…

MALICIOUS

PDF

35.6 KB Authoring application: 204G159G162G204G195G168G207G153G207G144G198G159G198G159G198G159G198G153G198G159G147G198G198G153G147G201G204G159G150G204G198G159G147G198G198G153G153G156G144G201G165G207G147G195G147G198G147G198G150G159G
MD5: b9077fcac6899a431f1930089f592086 SHA-1: 69236b2c5b1a179cd55480501846f4ff5adaf7c4 SHA-256: 03bdca2cef60f144a26fc925d98d4905d9ca1cef7008c3bdec300cace80a4ee3
120 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript that is heavily obfuscated using String.fromCharCode and numerical encoding. The ML classifier and PDF JavaScript exploit cluster heuristics indicate malicious intent. The script's primary function appears to be downloading and executing a secondary payload, as suggested by the obfuscated string concatenation and the overall exploit cluster findings. The specific URL for the payload download could not be reliably reconstructed due to the obfuscation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 7

  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • 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)
  • PDF paints image(s) but contains no text operators info PDF_IMAGE_ONLY_LURE
    PDF has 1 image XObject(s) and the content stream contains no text-emitting operators (BT/ET, Tj, TJ, ', ") in either raw bytes or decompressed streams — this is the screenshot-as-PDF pattern used to bypass text-based scanners and to deliver instructions purely through rendered pixels. It is informational unless paired with invisible links or risky URI context.
  • 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/xap/1.0/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/pdf/1.3/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0099_000.js
575d0bdd008d8572f586a62acebd6d1e2a336885188cd717a7b33f5bd1ab0215		 pdf-javascript-stream PDF /JS object 99 at offset 0x7FA7 11272 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).

Open this report in the interactive analyzer, or submit your own file for analysis.