Malicious PDF — malware analysis report

Static analysis result for SHA-256 839e556109c8a70c…

MALICIOUS

PDF

15.0 KB Created: 2009-11-15 19:41:70 Authoring application: PDF Library 4.3.9 (via PDF Library 3.9.7)
MD5: e75f872b79eaca3dcaf574ecd0669924 SHA-1: f194f732a8fc13ff33f19067c6d8ba2199bf0dd4 SHA-256: 839e556109c8a70ca9f2fd822591724d57f007408cd24e56d5e990106c550e85
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file was flagged by multiple heuristics, including ML classifiers and ClamAV, indicating malicious content. Specifically, the presence of embedded JavaScript actions and streams points to an attempt to execute code. The ClamAV detection of 'Win.Trojan.Agent-36166' strongly suggests this is a known trojan. The embedded JavaScript is likely responsible for downloading and executing a second-stage payload.

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
4511330686437327fd7ad00976a77573f9da279ec110daaa7cbfb587f87640d7
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 83718 bytes
Detection
ClamAV: Win.Trojan.Agent-36166
Obfuscation or payload: unlikely