Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd4ecdca52515f40…

MALICIOUS

PDF

6.1 KB Authoring application: Favib rela (via Pipnolpamok)
MD5: eedaeed1ba9e295f4e423a3a5c3454c5 SHA-1: eeaf6d531afe686b903a577c7174d3f4040daf0e SHA-256: fd4ecdca52515f40ed27407869ac7273c7af1773756d0aa128dad510a1e83392
166 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, indicating malicious content. The presence of embedded JavaScript, identified by PDF_JAVASCRIPT and PDF_JS heuristics, suggests an attempt to execute arbitrary code. The ClamAV detection of 'Pdf.Exploit.Agent-36174' further supports this. The JavaScript stream is likely responsible for exploiting a vulnerability within the PDF reader to download and execute a secondary payload.

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