Malicious PDF — malware analysis report

Static analysis result for SHA-256 6291b98eb4bf6104…

MALICIOUS

PDF

6.1 KB Authoring application: Favib rela (via Pipnolpamok)
MD5: 40e873505b7abf61086ea084b028e749 SHA-1: a005c4502980118a3c9bdbf15b8b2060b42c6bf1 SHA-256: 6291b98eb4bf6104f349f532548dd4bd8317693416a7e82588cb1783ecaf6f5a
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, identified by multiple heuristics and ClamAV detection as malicious (Pdf.Exploit.Agent-36174). The JavaScript code appears to be designed to download and execute a second-stage payload, indicated by its obfuscated nature and the use of functions like 'getPageNthWord'. The ML classifier also strongly flagged this PDF as malicious. Given these indicators, the primary attack pattern is likely exploitation via a malicious attachment.

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