Malicious PDF — malware analysis report

Static analysis result for SHA-256 a067d54773aee850…

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: dbd9d404d547a489bd750c8160d961df SHA-1: c50e40023f928c446107f904b2534c4224dae575 SHA-256: a067d54773aee850367a41e7a3c9c46dd9eb2982f31359c9459a94c1228dcf71
166 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Win.Trojan.Agent-36166'. The presence of embedded JavaScript, indicated by PDF_JAVASCRIPT and PDF_JS firings, suggests the script is responsible for executing the malicious payload. The ML classifier also strongly indicated maliciousness. The exact behavior of the JavaScript could not be determined due to its obfuscation, but the overall pattern points to a downloader or dropper.

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
acd66486d8de2dcd2580843813d54e95e359da9373c337868bd9c0a514920364
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 74436 bytes
Detection
ClamAV: Win.Trojan.Agent-36166
Obfuscation or payload: unlikely