Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b989116fabe19f6…

MALICIOUS

PDF

14.5 KB Created: 2009-11-15 19:41:70 Authoring application: PDF Library 4.3.9 (via PDF Library 3.9.7)
MD5: 01f69c5ae58647b34250fdb9b091579f SHA-1: e55669f1b11cbfdcccc52aef089d17198329ba40 SHA-256: 0b989116fabe19f68b03d552f833da2c6d7549a308221630d718f64b73645c1a
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF file contains embedded JavaScript, flagged by multiple heuristics and a machine learning classifier as malicious. ClamAV also detected it as Win.Trojan.Agent-36166. The JavaScript appears to be obfuscated but is likely responsible for downloading and executing a secondary payload, a common technique for malware distribution. Given the nature of the file and its embedded script, it is highly probable that this was delivered as a spearphishing attachment.

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
a0b4a115e412cf1376decac1c75946f16f28f44cfa18cfa902ead5b9a6a9635a
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 75088 bytes
Detection
ClamAV: Win.Trojan.Agent-36166
Obfuscation or payload: unlikely