Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e3a7bf2d3a6d28f…

MALICIOUS

PDF

3.9 KB
MD5: e908a53a7ba34392863de2cabfaf425d SHA-1: 4a9c014807c3555f73b553b062dd301cdce0d92a SHA-256: 8e3a7bf2d3a6d28f610699b155c36711ee26d8138389db6e94d0eea96e63a052
142 Risk Score

Malware Insights

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

The file is a PDF identified as malicious by ClamAV (Pdf.Exploit.Agent-36178) and a machine learning classifier. Heuristics indicate the presence of embedded JavaScript, which is likely used to exploit PDF vulnerabilities. The use of ASCIIHexDecode and ASCII85Decode filters, along with String.fromCharCode, suggests obfuscation techniques common in PDF exploits. The ML classifier's high confidence score further supports the malicious nature of the document.

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