Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d3cb188e8eeaf8f…

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: 868072796b4d4bd7c9ca46f6cdb71908 SHA-1: 56bd0ff3775289cbdd34514146052811a5ec5901 SHA-256: 5d3cb188e8eeaf8fb159f8d795b8d54b19f556ec60bd53109f988e20f1965742
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript 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. Embedded JavaScript, which is heavily obfuscated, is present and likely responsible for downloading and executing a secondary payload. The presence of JavaScript and the nature of the detection suggest a common malware delivery pattern.

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
e6848d26d7440a7f58f71545d4536eff8ff1378081648797cb0fd18f2a9f7354
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 74571 bytes
Detection
ClamAV: Win.Trojan.Agent-36166
Obfuscation or payload: unlikely