Malicious PDF — malware analysis report

Static analysis result for SHA-256 02c83e524021b042…

MALICIOUS

PDF

1.6 KB
MD5: 9514852878cde4e33ff4f787075b3dc0 SHA-1: 87c9b229c81e578ea3afd934e97b4948a172e8bd SHA-256: 02c83e524021b042623978f1264f3308827c7f8fee5159e5957c2217855d16dc
216 Risk Score

Malware Insights

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

This PDF file contains obfuscated JavaScript code that utilizes eval() and String.fromCharCode(), indicating an attempt to exploit vulnerabilities and execute arbitrary code. The presence of a JavaScript exploit cluster and ML classification strongly suggests malicious intent. The embedded JavaScript file, 'javascript_obj0009_000.js', is the primary artifact for further analysis, likely containing the payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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.
  • 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
6fb1b67e0da47f88726dcff89b932158914ef6b750d620e464970a4c79d3a221
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).