Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f1b12af6fbf2c7b…

MALICIOUS

PDF

6.1 KB Authoring application: Favib rela (via Pipnolpamok)
MD5: 66889fb0c6f0346420d01fe14eb45c7e SHA-1: a41dadfdcf257442388b35d3ca3a586850c00ae5 SHA-256: 5f1b12af6fbf2c7be5f7ffa2339fdda9ff4b93a950d2a0110f38d9191fbe7e39
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, indicated by multiple heuristic firings and the presence of a javascript_obj0015_000.js file. The JavaScript code appears to be obfuscated but is designed to execute and likely download a further stage. ClamAV detection as Pdf.Exploit.Agent-36174 further confirms its malicious nature, suggesting it exploits a known PDF vulnerability.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • ClamAV: Pdf.Exploit.Agent-36174 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36174
  • 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_obj0015_000.js
d2679f3f15d6e025ee8c17fa18b94c5a0f309ff0925fe97138da94e5b5bbdf34
pdf-javascript-stream PDF /JS object 15 at offset 0x1281 1504 bytes
Detection
ClamAV: Pdf.Exploit.Agent-36174
Obfuscation or payload: unlikely