Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd7424fe5a3ed19a…

MALICIOUS

PDF

118.7 KB
MD5: edd76626de60f5371d6e9eda2821da5e SHA-1: c6fe3f8a7114c8f42b810a1347d0f4ab136403fc SHA-256: cd7424fe5a3ed19a6da6510888a783386ac777f01fae97b782a76f4b65b79611
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF contains embedded JavaScript that utilizes eval() and String.fromCharCode, indicating an attempt to obfuscate and execute malicious code. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically an exploit targeting PDF vulnerabilities. The primary attack pattern involves leveraging JavaScript within the PDF to achieve code execution.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL
    PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
  • 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_obj0006_000.js
523da28163027ccf36f0dd827b73e5bddbb9fbece73df8e87f73ef7dd5debf41
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626624 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).