Malicious PDF — malware analysis report

Static analysis result for SHA-256 a17aae38c6eea5d4…

MALICIOUS

PDF

3.8 KB
MD5: df9193c146003598461c84add82b6c63 SHA-1: eebc41558e222d8e0323511f6cd51fdc2fbe032b SHA-256: a17aae38c6eea5d41360ad4947f153214d7bbcd9ca78af79edef86c91c4f40ba
142 Risk Score

Malware Insights

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

The file is identified as a malicious PDF by ClamAV (Pdf.Exploit.Agent-36178) and a machine learning classifier. Heuristics indicate the presence of JavaScript actions and embedded JS streams, along with ASCIIHexDecode and ASCII85Decode filters, which are commonly used in PDF exploits. The ML classifier's high confidence score further supports the malicious nature of the file. The specific exploit mechanism is not detailed, but the presence of JavaScript suggests it aims to execute code, likely to download and run 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