Malicious PDF — malware analysis report

Static analysis result for SHA-256 fed86129c7566d24…

MALICIOUS

PDF

3.9 KB
MD5: 392462a9de5eeb3d98dfce8b7f75ebb2 SHA-1: ccfb72b65f0244cf6c85d504a87f83e1ffbdce45 SHA-256: fed86129c7566d244061b075f96e35ee3c370cd29bd075f7b580c307f6b1c203
142 Risk Score

Malware Insights

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

The file is a PDF that has been flagged by a machine learning classifier and ClamAV as malicious, specifically identified as Pdf.Exploit.Agent-36178. Multiple PDF-specific heuristics indicate the presence of obfuscated JavaScript and exploit-related filters, suggesting it attempts to leverage vulnerabilities within the PDF reader. The primary attack pattern involves exploiting these vulnerabilities to execute malicious code, likely leading to the download and execution of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • ClamAV: Pdf.Exploit.Agent-36178 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36178
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • ASCII85Decode filter (with exploit indicators) low PDF_FILTER_85
    ASCII85 encoding filter present alongside exploit delivery indicators — uncommon outside of obfuscation