Malicious PDF — malware analysis report

Static analysis result for SHA-256 56c4412d496d1eca…

MALICIOUS

PDF

5.2 KB
MD5: caca87ba193daa1c048249c28dc5352d SHA-1: f69b93bf48c9a415b18ff44c32400ed1c10260fb SHA-256: 56c4412d496d1ecac01df16a92960ee43296d384c2e1baa32b7268b0f5356cf2
144 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ClamAV with the signature 'Pdf.Exploit.Agent-36178'. Static analysis revealed the presence of JavaScript actions and embedded JS streams, utilizing filters like ASCIIHexDecode and ASCII85Decode, which are common indicators of PDF exploits. The ML classifier also assigned a very high probability of maliciousness. The exact attack pattern is not fully discernible due to the lack of readable document body text, but the presence of exploit-related heuristics strongly suggests it's designed to deliver a secondary payload.

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.