Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f407cb874ba9dd8…

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: b11d12d765ff2ea84894a011dae54293 SHA-1: d679687f6bb438244e047d6366a50976bbcf6e94 SHA-256: 6f407cb874ba9dd8459901e8226d5112770b77ab0bc82d2aecc094b1c006eb14
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, identified by heuristics and ClamAV, which is a common technique for delivering malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The JavaScript is heavily obfuscated, but its presence and the overall file characteristics suggest it's designed to download and execute a secondary payload, consistent with 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
fed0eff67405e5c3bd0800e885b74c984e94167a05e4e7fea0330cd25e5d08b5
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 74220 bytes
Detection
ClamAV: Win.Trojan.Agent-36166
Obfuscation or payload: unlikely