Win.Trojan.Agent-36166 — PDF malware analysis

Static analysis result for SHA-256 18886677874e32fd…

MALICIOUS

PDF

14.4 KB Created: 2009-11-15 19:41:70 Authoring application: PDF Library 4.3.9 (via PDF Library 3.9.7)
MD5: 4cbe4108a0fee0b4ec3f60c7b8c38fe3 SHA-1: 0cde975887f8970a9e1ddb1f3149043c4fc7b2ad SHA-256: 18886677874e32fd5bbfb64d1ea4bcb12e0083dca34454bd7994e9c000240959
166 Risk Score

Malware Insights

Win.Trojan.Agent-36166 · confidence 95%

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

The PDF file was flagged as malicious by multiple heuristics and a machine learning classifier, with ClamAV identifying it as Win.Trojan.Agent-36166. It contains embedded JavaScript, which is a common method for exploiting PDF vulnerabilities to achieve code execution. The JavaScript appears to be obfuscated but is likely responsible for downloading and executing a secondary payload, consistent with the behavior of a trojan agent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 4

  • ClamAV: Win.Trojan.Agent-36166 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Trojan.Agent-36166
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
9ad901fc23a3485d29b3f0255dced0f81f9c791ead3c97a39ed49dbd313a8ac0
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 74402 bytes
Detection
ClamAV: Win.Trojan.Agent-36166
Obfuscation or payload: unlikely