Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1568c4f46a44831…

MALICIOUS

PDF

2.2 KB
MD5: e6d3d618d38124c801bce4278e45d8a4 SHA-1: 32d7ee4578ad0cde5524dac1c5d53a85b4732519 SHA-256: d1568c4f46a448311e6bb833fa5ae0e989ae6c92dd5385a66c838ec8b521015b
198 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1027 Obfuscated Files or Information

This PDF file was flagged as malicious by ClamAV with the signature Pdf.Exploit.Agent-36082. Static analysis revealed embedded JavaScript with multiple obfuscation techniques, including eval(), unescape(), and String.fromCharCode(). The ML classifier also strongly indicated maliciousness. The primary attack vector appears to be the exploitation of a PDF vulnerability to run obfuscated JavaScript, which is likely responsible for downloading and executing a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36082 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36082
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj111611_000.js
772da696bdb365f3f1eb4ea6af881baad391be62f3591b19f2f9827fcc4c9b53
pdf-javascript-stream PDF /JS object 111611 at offset 0x7DA 479 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
5964fd0b660a79fb32d958236ad4076e6109bd163e7367672e5cd27b7d4de217
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2816 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).