Malicious PDF — malware analysis report

Static analysis result for SHA-256 c655fd010a991414…

MALICIOUS

PDF

5.2 KB
MD5: e65e42b672c027a1d540f35cb4f9e9f2 SHA-1: 8b4a5e4ca4811ab25fb145a34c31a7c8a8518be7 SHA-256: c655fd010a991414bfe80ba6706360e96f0a2623c504f212468ff600ef696122
144 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating it contains an exploit. The presence of PDF-specific heuristics like PDF_JAVASCRIPT, PDF_JS, PDF_FROMCHARCODE, PDF_FILTER_HEX, and PDF_FILTER_85 strongly suggests the exploitation of a PDF vulnerability. The embedded JavaScript, likely obfuscated, is responsible for executing the exploit, leading to the detection of 'Pdf.Exploit.Agent-36178'.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.