Malicious PDF — malware analysis report

Static analysis result for SHA-256 d22b92b090540918…

MALICIOUS

PDF

3.8 KB
MD5: f73d1daed5d0e1796baee548146ab0a2 SHA-1: 801635a2b4cba51a347fa5a7727299e61ea36c6c SHA-256: d22b92b090540918d179743807e543868c6145b2bcf3045b40565b0470435f49
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 multiple heuristics and a machine learning classifier as malicious. ClamAV specifically identifies it as Pdf.Exploit.Agent-36178, indicating it contains an exploit. The presence of JavaScript actions and embedded JS streams, along with the use of ASCIIHexDecode and ASCII85Decode filters, are common techniques for obfuscating malicious code within PDFs. The ML classifier's high score further supports the malicious nature of the file.

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